Option- 1: Nepenthes is a type of insectivorous plant commonly known as pitcher plants. They have modified leaves in the form of pitchers that trap and digest insects.

Option- 2: Utricularia, also known as bladderworts, are insectivorous plants that have small bladder-like structures that suck in small organisms like insects and protozoa.

Option- 3: Drosera, also known as sundews, are insectivorous plants that have sticky hair-like structures on their leaves. When an insect lands on these leaves, it gets trapped and eventually digested by the plant.

Option- 4: Cuscuta, also known as dodder, is a parasitic plant and not an insectivorous plant. It does not derive nutrients from insects but rather attaches itself to host plants to obtain nutrients.

Therefore, option 4 (Cuscuta) is not an insectivorous plant.