Answer:

Carnivorous plants are unique types of plants that have adapted to obtain nutrients by trapping and digesting small insects and other organisms. They have evolved this mechanism due to the lack of nutrients, particularly nitrogen, in their natural habitats. One such carnivorous plant is the Venus Flytrap.

Venus Flytrap:
- The Venus Flytrap is a carnivorous plant native to the subtropical wetlands of the United States.
- It is a small plant with leaves that have modified into trapping mechanisms.
- The traps consist of two lobes with sensitive trigger hairs on the inner surface.
- When an insect or small organism touches the trigger hairs, the lobes snap shut, trapping the prey inside.
- The plant then secretes enzymes to digest the prey and absorb the nutrients.
- Venus Flytraps primarily feed on small insects, such as flies and spiders.

Other options:
a) Cactus: Cacti are not carnivorous plants. They are adapted to survive in arid environments and store water in their fleshy stems.
b) Sunflower: Sunflowers are not carnivorous plants. They belong to the family Asteraceae and are known for their large, showy flowers and edible seeds.
d) Orchid: Orchids are not carnivorous plants. They are a diverse family of flowering plants known for their beautiful and often fragrant flowers. Orchids obtain nutrients through their roots like most other plants.

Adaptations of carnivorous plants:
Carnivorous plants have developed various adaptations to capture and digest their prey. Some common adaptations include:
1. Trapping mechanisms: Plants like the Venus Flytrap have specialized leaves that form traps to catch prey. These traps may close rapidly or have sticky surfaces to prevent escape.
2. Digestive enzymes: Carnivorous plants produce enzymes that help break down the captured prey into simpler compounds that can be absorbed by the plant.
3. Modified leaves: The leaves of carnivorous plants have evolved to perform functions other than photosynthesis. They may have hairs or glands that secrete digestive enzymes or nectar to attract prey.
4. Reduced dependence on soil nutrients: Carnivorous plants have reduced their reliance on obtaining nutrients from the soil due to the lack of availability in their habitats. They have developed alternative ways to obtain nitrogen and other essential nutrients from insects and other prey.

In conclusion, the Venus Flytrap is a carnivorous plant that has evolved unique adaptations to capture and digest small insects as a source of nutrients.