according to the passage predator can attack when it is in any one of the sphere(imagine fish is at center of a sphere),also they mentioned three fishes overlap as much as possible that means the three spheres coincide one on other.
In option A ,the possibility for predator to attack as a whole is not much greater than(there is no difference) attacking individual.
remaining options can't be inferred

Thank you.

Given: Consider three fish swimming together in a school. The space within which each fish can be seen by predator Y is defined by a sphere centered on the fish and having a radius that is the maximum distance Y can see. The school is vulnerable to attack when Y is within one of the three spheres. The spheres overlap to a great extent, since the fish are in a compact group.

Asked: Which of the following is a reliable inference to be drawn from the passage above?

Since Y >> distance between fishes ; Since the fish are in a compact group and the spheres overlap to a great extent
Vulnerability of a single fish ~ Vulnerability of the group of fish ~ Vulnerability of the school

(A) The vulnerability to attack of the school as a whole is not much greater than the vulnerability to attack of any one fish in the school.

(B) There is less chance that predator Y will attack a school of four fish than that it will attack a school of three fish.
Out of scope
(C) Fish who swim I schools are less likely to be devoured by predators than are fish who do not swim in schools.
Out of scope
(D) The maximum distance at which an individual fish is visible depends less on the size of the fish than on whether the fish is swimming in a school.
Irrelevant
(E) The maximum distance at which predator Y can see its prey is increased if Y is itself swimming in a school of Y’s.
Out of context

IMO A

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