What are Type I and Type II errors in hypothesis testing?

• A. Type I = reject a true null; Type II = fail to reject a false null.
• B. Type I = fail to reject a true null; Type II = reject a false null.
• C. Type I = reject a false null; Type II = accept a true null.
• D. Type I = fail to reject a false null; Type II = fail to reject a true null.

Answer: (A)