In a hypothetical environment, fishes called pike-cichlids are visual predators

Question

In a hypothetical environment, fishes called pike-cichlids are visual predators of algae-eating fish (i.e., they locate their prey by sight). If a population of algae-eaters experiences predation pressure from pike-cichlids, which of the following should least likely be observed in the algae-eater population over the course of many generations?

I know the answer is "Selection for larger female algae-eaters, bearing broods composed of more, and larger, young" but can you provide an explanation of why this is the correct answer?

The other answers were:

In a hypothetical environment, fishes called pike-cichlids are visual predators of algae-eating fish (i.e., they locate their prey by sight). If a population of algae-eaters experiences predation pressure from pike-cichlids, which of the following should least likely be observed in the algae-eater population over the course of many generations?

A. Selection for drab coloration of the algae-eaters
B. Selection for nocturnal algae-eaters (active only at night
C. Selection for algae-eaters that are faster swimmers
D. Selection for larger female algae-eaters, bearing broods composed of more, and larger, young
E. Selection for algae-eaters that become sexually mature at smaller overall body sizes

Explanation / Answer

In order to counteract the predation pressure, during the course of time the progenies of algae eaters in successive generations might tend to be selected for following characteristics:

A- Coloration to warn the predators using it as a means of self defense.

B- Nocturnal algae eaters as these will reduce the frequency of attack by the pike-cichlids predators because they can locate the prey by sight.

C- Fast swimmers in order to escape and be saved from being preyed.

E- Being sexually matured at smaller overall body size in order to combat the excessive predation and escape the sight of the predator.

Option D i.e., selection for larger female algae-eaters, bearing broods composed of more, and larger, young would be observed less likely because the larger body size of the female algae eaters is a conspicuous trait and as the predators prey by sight, the larger fishes will easily be located by them. On other hand, larger female fishes bears better broods which has an important role in replenishing the wiped out population of the preyed animals. Unfortunately, the larger brood size counts only when they large bodied fishes are spared by the predators which seems difficult in the given circumstances because its mentioned that algae eater population is under the predation pressure and thus the frequency of this selection would be very rare.

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