The correct answer is option 4, Drosera. Drosera is a genus of carnivorous plants that are commonly known as sundews. These plants have specialized leaves that are covered in small, glandular hairs that produce a sticky, sweet-scented secretion. When insects or other small organisms come into contact with the sticky secretion, they become trapped and eventually digested by enzymes produced by the plant. Drosera plants are found in various habitats, including bogs and wetlands, and they are able to supplement their nutrient requirements by capturing and digesting insects. Other options provided in the question are not insectivorous plants. Balanophora is a parasitic plant, Rafflesia is a parasitic flowering plant, and Orobanche is a parasitic plant that primarily targets the roots of other plants.