Insectivorous plants are those that obtain their nutrients by trapping and digesting insects and other small prey. Monotropa is not an insectivorous plant, as it does not derive its nutrition from insects or other small prey.

Explanation:

- Monotropa: Monotropa, also known as ghost plant or Indian pipe, is a parasitic plant that obtains its nutrients from the roots of other plants. It does not trap and digest insects, and therefore, it is not an insectivorous plant.
- Drosera: Drosera, also known as sundew, is an insectivorous plant that traps insects with its sticky leaves. The plant then secretes enzymes that digest the trapped insect and absorb the nutrients.
- Utricularia: Utricularia, also known as bladderwort, is an aquatic insectivorous plant that traps small aquatic animals, such as water fleas and mosquito larvae, in its bladder-like traps. The plant then secretes enzymes that digest the trapped prey and absorb the nutrients.
- Nepenthes: Nepenthes, also known as pitcher plant, is an insectivorous plant that traps insects in its pitcher-shaped leaves. The plant secretes digestive enzymes into the pitcher, which break down the trapped insects into nutrients that the plant can absorb.

Therefore, the correct answer is option 'A' Monotropa, which is not an insectivorous plant.

It is because cascuta dose not eats insect.It is a host... And take its nutrition from trees..