An Li reached puberty at age 12, and John Smith retired at age 65. An Li's and John Smith's experiences are examples of:

A. normative events.

B. non-normative influences.

C. critical periods.

D. risk factors.

I chose A. but now reading a little more into it, I'm not sure if B is the right answer. Please help.

A is correct.

http://www.indiana.edu/~famlygrf/units/family.html