in a species in which females provide all the needed food and protection for the young..?

Question

a. males are likely to be promiscuous
b. mating systems are likely to be monogamous
c. mating systems are likely to be polyandrous
d. males most likely will show sexual selection
e. females will have a higher Darwinian fitness than males

Answer 1

It would have to be "e".

The females are doing all the work, they are successful at it due to evolution.

Answer 2

Think about it this way - imagine a culture where women take care of the kids and the guys are out every night enjoying themselves. What are they likely to do? Contrast this to a society where men are expected to stay home and help with the children. The answer should come to you pretty quickly.

(Actually there are two correct answers above, but you're probably supposed to pick just one. Also, remind your teacher that the concept of 'Darwinian fitness' is a little outdated.)