The correct answer is (c) (ii) and (iii).
Explanation:
A food chain consists of a series of organisms where one eats the other, with the energy transfer from one level to the next. In a valid food chain, there must be a producer (like grass) that is eaten by a primary consumer (like a rabbit), then a secondary consumer (like a snake), and so on.
In option (ii), “plankton, man, fish, grasshopper,” while the organisms are connected, the chain is not entirely logical. Grasshopper is a terrestrial insect, not part of the aquatic ecosystem where plankton and fish exist. Additionally, man is not a primary consumer of plankton or fish directly.
In option (iii), “wolf, grass, snake, tiger,” all are carnivores. There is no herbivore to eat the grass, making this group not a constituent of a food chain.
In option (i), “Grass, lion, rabbit, wolf,” this represents a valid food chain as grass is the producer, rabbits eat grass, lions eat rabbits, and wolves can prey on both rabbits and lions.
In option (iv), “Frog, snake, eagle, grass, grasshopper,” this also represents a valid food chain with grass as the producer, grasshopper feeding on grass, snake eating frogs, and eagle preying on snakes.