The alternative hypothesis is best described as?

• A. Observed differences are due to chance
• B. Observed differences are not due to chance
• C. There is no difference
• D. The null is always false

Answer: (B)

In hypothesis testing, you compare two competing statements: the null, which assumes no real difference or effect, and the alternative, which claims there is a real difference or effect beyond random variation. The alternative is best described as observed differences are not due to chance, meaning the data point to a true effect rather than just random fluctuations. When the test shows statistical significance, you reject the null in favor of this alternative.

The other statements reflect the null or are incorrect about the null: differences due to chance align with the null hypothesis, “there is no difference” is a null claim, and “the null is always false” isn’t true because there are many situations where the data do not provide enough evidence to reject the null.