What is the benefit of taking the same measurement several times in science?

Correct answer: Reducing the effect of random errors

The correct answer is option C: repeated measurements reduce the effect of random errors. A measurement can be affected by small unpredictable variations, such as reaction time, slight instrument fluctuation, or difficulty reading a scale. If the same quantity is measured several times under the same conditions, the readings may be slightly different. Their average is often closer to the true value because positive and negative random deviations partly cancel. Option A is wrong because science does not choose a different answer merely because readings vary; it records and analyses the readings. Option B is wrong because repeating a measurement does not require changing its unit. Option C is correct because repetition improves reliability by reducing random variation, although it cannot automatically remove systematic error. Option D is wrong because measurements are evidence, not something to remove. A useful memory cue is: repeat, compare, and average; do not select whichever reading looks convenient.