You study Crab-eating Macaques so you know that females produce offspring from age 3 to 20 years old. You suspect their offspring get larger over time, so you follow an SRS of females for 2 decades to compare the weight of their first baby to the last to see if they are indeed different.

In addition to choosing the correct procedure, would this study be prospective or retrospective?

Select one:

a.)Two-sample T-Test, retrospective

b.)T-test for difference in matched data, prospective

c.)T-Interval for the difference in matched pairs (paired data), retrospective

d.)Two-sample T-Interval, prospective