Which of the following statements is true about p-values?

Correct answer: D. It is the probability of the sample data arising by chance if the null hypothesis were true

• A. ❌ P-value is related to but not identical to the Type I error rate (alpha).
• B. ❌ Square root of variance is the standard deviation — a measure of variability, not a p-value.
• C. ❌ The p-value assumes the null hypothesis IS true, not false.
• D. ✅ Correct. The p-value is the probability of obtaining results at least as extreme as observed, assuming the null hypothesis is true. p < 0.05 means <5% chance the results arose by random chance alone.

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