Nature and meaning of science

Correct answer: A. Lack of falsifiability

A scientific explanation must allow the possibility of an opposing result. Treat falsifiability as a key criterion.

Correct answer: A. Replace definitely with the evidence suggests

Scientific language should match the strength of evidence. Identify cautious conclusion wording.

Correct answer: A. Repeatability is strong and external validity is limited

Results may be consistent in artificial settings but application to real life may be limited. Distinguish the two qualities.

Correct answer: A. Define clear and measurable criteria

The direct answer is A: define clear and measurable criteria. An operational definition explains exactly how a scientist will recognize or measure a variable. For example, instead of saying that a plant is healthy, the study might define health as a particular height, number of leaves, or mass measured in a stated way. If observers use different meanings, their records cannot be compared reliably. Option A is correct because pre-decided, observable, measurable rules reduce observer differences and improve consistency. Option B is wrong: using fewer observers does not repair an unclear definition and may reduce useful checking. Option C is wrong because an average can summarize numbers but cannot decide what was measured or remove inconsistent meanings. Option D is wrong and scientifically unacceptable because deciding the outcome afterward invites bias. The correct procedure is to define the variable and its measurement rule before collecting results. Memory cue: first define how to measure, then measure.

Correct answer: A. Testing under different conditions and populations

Testing in different settings examines external validity. Look for diverse testing when judging generalisation.

Correct answer: A. The effect may be real but its practical importance should be assessed separately

Precision may clarify the existence of an effect but not its importance. Distinguish effect size from usefulness.

Correct answer: A. Small studies may be exaggerating the effect

Small studies may be more affected by chance and selective publication. Examine study size and publication bias.

Correct answer: A. Examine the instrument and procedure and document the cause

A claim of error should be based on evidence and documentation. Choose transparent error analysis.

Correct answer: A. Careful observational studies and multiple independent lines of evidence

Within ethical limits observations models and natural comparisons can be useful. Identify safe alternative methods.

Correct answer: A. The meaning and comparison of measurements become unclear

Units clarify the magnitude and comparability of measurements. Treat units as essential with numerical values.

Correct answer: A. Acceptance is informative but independent verification is limited

Expert review is important but transparent data strengthen independent checking. Distinguish authority from evidence.

Correct answer: A. The model may become more complex but less testable

An unmeasurable variable may make a model arbitrary and untestable. Examine testability along with complexity.

Correct answer: A. Attention itself may influence the outcome

Different levels of attention may be confused with the treatment effect. Compare contact and care across groups.

Correct answer: A. Acknowledge uncertainty and state the need for further investigation

When evidence is balanced uncertainty is scientifically appropriate. Match confidence to the evidence.

Correct answer: A. It reduces the risk of removing data arbitrarily after seeing results

Predefined exclusion criteria improve transparency and objectivity. Recognise advance planning.

Correct answer: A. Whether the result arises from an instrument-specific error or limitation

An instrument-specific result may arise from a unique error or sensitivity. Seek verification with alternative instruments.

Correct answer: A. The evidence supported the hypothesis

A scientific study may support a hypothesis but usually does not provide absolute final proof. Choose cautious language.

Correct answer: A. Identifying the true treatment effect

Changing groups may blur the relationship between treatment and outcome. Examine adherence to group assignment.

Correct answer: A. The model assumptions still need testing against real evidence

Simulation is useful but its assumptions and predictions should be tested with real data. Understand the link between models and evidence.

Correct answer: A. There is evidence of benefit but overall safety cannot be determined

Benefit and safety are separate outcomes and both require measurement. Identify incomplete outcome reporting.

Correct answer: A. The quality of the studies

In scientific conclusions, the quality of studies matters more than their number alone. Strong studies use appropriate methods, adequate samples, controlled conditions, reliable data, and steps to reduce bias. Therefore, even if they are fewer, stronger studies should be given priority. A larger number of studies is not enough if those studies have weak designs or are biased. Exam tip: When judging evidence, check the study method and reliability first.

Correct answer: A. It has broader explanatory scope

A better theory retains earlier successful explanations while accounting for new evidence. Recognise scientific refinement.

Correct answer: A. It indicates how much confidence in the conclusion is justified

Uncertainty clarifies evidence limits and conclusion strength. Treat it as scientific honesty.

Correct answer: A. Science can provide factual outcomes while decisions may also involve social values

Scientific evidence describes outcomes while decisions about proper use may also involve ethical and social values. Distinguish facts from values.

Correct answer: A. It is a collective knowledge process developed through evidence reasoning creativity testing criticism ethics uncertainty and revision

Science includes knowledge as well as the processes of creating testing limiting and improving it. Recognise all dimensions of science.