I know the answers. Can someone explain what the options underlined are correct and the other are not? Why is D correct and the others are not?

I know the answers. Can someone explain what the options underlined are correct and the other are not?

Why is D correct and the others are not?

The forelimbs of early mammals were similar in all features except

a.    embryonic origin

b.    position on the body

c.    number

d.    function

e.    composition

Why are the others correct and D is the exception?

7. Four of the five answers below are used in describing species. Select the exception.

a. interbreeding

b. sexual reproduction

c. populations

d. natural selection

e. color

Why is E the exception and the others are correct?

Four of the five answers listed below can function to isolate populations. Select the exception.