What should be done when an unexpected result is obtained during an experiment?

Correct answer: Record it accurately

The direct answer is D: record it accurately. An unexpected result is still an observation and may provide important evidence. Science does not allow a researcher to remove, alter, or hide a result merely because it was not predicted. Step by step: observe the result; write exactly what happened, preferably with measurements, units, date, and relevant conditions; check the equipment and method if necessary; repeat the experiment when appropriate; then discuss whether the finding supports the hypothesis. Option A is wrong because deleting an unexpected result creates an incomplete record. Option B is wrong because changing the result is falsification and makes the evidence unreliable. Option C is wrong because hiding it prevents others from judging the investigation and may conceal a genuine effect or a procedural problem. Option D is correct because accurate recording preserves the evidence while later checking can determine its meaning. The result may be due to a real effect, random variation, or an error, but that decision must come after examination. Memory cue: unexpected does not mean unusable—record first, investigate next.