Give reasons.

(a) It is very important to preserve the prey-predator chains.

(b) The single crop method can prove harmful.

(a) It is very important to preserve the prey predator chains as in a forest, tiger alone cannot survive. Herbivores are needed for the survival of carnivores. Predators cannot survive in the absence of prey. Hence, it is necessary to continue the prey-predator cycle.
The example of prey-predator cycle is shown below:

(b) Single crop method is used by farmers to get large harvest and high prices but the biodiversity in the plant kingdom is endangered. The traditional multi crop farming is helpful in maintaining biodiversity.