In a pond with plenty of food and space, the feeding efficiency of on…

The correct answer is Option (1) → Resources need not be limiting for competition to occur.

Competition need not wait for resources to run short. In interference competition, one species lowers the feeding efficiency of another just by its interfering and inhibitory presence, even when food and space are abundant. The pond here has plenty of food and space, yet the first species feeds less well when the second is near.

Option (1) Resources need not be limiting for competition to occur. — Correct. The food and space in the pond are plentiful, so the fall in feeding efficiency cannot come from a shortage. It shows that resources need not be limiting for competition to occur.

Option (2) The two species are avoiding competition by resource partitioning. — Incorrect. In resource partitioning, competing species share out a resource, for example by feeding at different times, and so avoid competition. Here one species is being harmed by the other, so competition is not being avoided.

Option (3) The first species has been released from competition by the second species. — Incorrect. Competitive release is the opposite case: a species spreads to a larger area when its superior competitor is removed. Here the second species is present and the first species is doing worse.

Option (4) The second species is a predator that keeps the first species under control. — Incorrect. A predator kills and eats its prey. Nothing in the observation shows the second species eating the first.

NCERT Extract:
Population Interactions – “… It is generally believed that competition occurs when closely related species compete for the same resources that are limiting, but this is not entirely true. … resources need not be limiting for competition to occur; in interference competition, the feeding efficiency of one species might be reduced due to the interfering and inhibitory presence of the other species, even if resources (food and space) are abundant.”