Question

Plants capable of growing in nitrogen-deficient soil is
(a) Orchids
(b) Ferns
(c) Insectivorous plants
(d) Rafflesia

Answer 1

Nitrogen, phosphorus, and potassium are the main macronutrients of plants, which help in the synthesis of organic molecules. These macronutrients obtained from soil and deficiency cause plant disease. The plant which grows in nitrogen-deficient soil shows the heterotrophic mode of nutrition.

Complete Answer:
Insectivorous plants are autotrophic plants but they behave like heterotrophs because they trap insects to supplement their nitrogen requirement. The insectivorous plant grows in swamp and bogs where the soil is deficient in nitrogen supply.

Additional information:
Insectivorous plants include nepenthes, sundew, venus fly trap, water flea trap, bladderwort, and butterwort.
Nepenthes is a well-known pitcher plant grown in the northeastern region of India. Plant leaf base is flat, the petiole is tendrillar and lamina is modified into the pitcher with an apex forming lid. The rim of the pitcher bears nectariferous glands that attract insects, the insect then slips into the pitcher and gets tumbled into the digestive fluid. The insect gets trapped into projecting hair and dies. These insects get decomposed by microorganisms and breakdown products are absorbed by the plant.
Sundew is a small herbaceous plant. Leaf surface and lamina bear club-shaped hairs, which is glandular and secrete sticky fluid at their tips. Insect alighting on the leaf due to glitter like fluid drops and get stuck. Enzymes secreted by hairs digest insects and products get absorbed by the leaf.
Venus flytrap grows in damp and marshy places. It has a rosette of radiating leaves. Lamina has two lobes that hinge to the midrib. Upper surface bear spines and digestive glands. When an insect touches the hair, the two lobes of the lamina fold rapidly. The insect gets trapped inside the spine and gets digested by digestive juices.
Rafflesia is also a heterotrophic plant but it is an example of root parasites. It has thread-like vegetative parts as root. The grape family is a common host for rafflesia from which they obtain nutrients. Rafflesia is the largest flower in the world with a diameter of one meter.

So, the correct answer is an Insectivorous plant.

Note: Insectivorous plants can survive normally without feeding on the insect. In the case of nitrogen deficiency, their growth gets retarded but nutrient supply for their survival gets fulfilled by carbon, hydrogen, and oxygen by photosynthesis.