Heterotrophic nutrition is found in
(a) Pistia
(b) Vallisnaria
(c) Drosera
(d) Opuntia

Options

A. Pistia
B. Vallisnaria
C. Drosera
D. Opuntia

Explanation

To solve the question about which organism exhibits heterotrophic nutrition, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Heterotrophic Nutrition**:
- Heterotrophic nutrition refers to the mode of nutrition where organisms cannot synthesize their own food and depend on other organisms for nutrition. This is in contrast to autotrophic nutrition, where organisms produce their own food (e.g., through photosynthesis).

2. **Analyze Each Option**:
- **(a) Pistia**: This is a type of aquatic plant. It is a hydrophyte and primarily relies on photosynthesis to produce its own food. Therefore, it does not exhibit heterotrophic nutrition.
- **(b) Vallisneria**: Similar to Pistia, Vallisneria is also an aquatic plant that relies on photosynthesis for its nutritional needs. It does not exhibit heterotrophic nutrition.
- **(c) Drosera**: This is known as the sundew plant and is classified as an insectivorous plant. Drosera captures insects and relies on them for nutrients, particularly nitrogen. This indicates that it exhibits heterotrophic nutrition.
- **(d) Opuntia**: Opuntia, commonly known as prickly pear, is a xerophytic plant that can survive in dry conditions. It primarily relies on photosynthesis for its nutritional needs, thus it does not exhibit heterotrophic nutrition.

3. **Conclusion**:
- Based on the analysis, the only plant that exhibits heterotrophic nutrition is **Drosera** (option c).

### Final Answer:
(c) Drosera

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