Which of the following are ammonotelic?

Options

A. Terrestrial amphibians
B. Land snails
C. Marine fishes
D. Aquatic insects

Answer

To determine which of the given options are ammonotelic, we need to understand the term "ammonotelic" and analyze each option accordingly.

### Step-by-Step Solution:

1. **Understanding Ammonotelism**:
- Ammonotelic animals are those that excrete nitrogenous waste primarily in the form of ammonia. This is common in aquatic animals because ammonia is highly soluble in water and can be easily diluted.

2. **Analyzing the Options**:
- **Option A: Terrestrial amphibians**:
- These animals typically excrete urea, making them ureotelic, not ammonotelic.
- **Option B: Land snails**:
- Land snails excrete nitrogenous waste in the form of uric acid, which classifies them as ureotelic.
- **Option C: Marine fishes**:
- Marine fishes can be divided into two categories: elasmobranchs (like sharks) which are ureotelic, and bony fishes which are generally ammonotelic. However, since not all marine fishes are ammonotelic, this option cannot be classified as ammonotelic.
- **Option D: Aquatic insects**:
- Aquatic insects, such as mayflies and dragonflies, excrete ammonia, making them ammonotelic.

3. **Conclusion**:
- Based on the analysis, the only group that is ammonotelic among the options provided is **aquatic insects**. Therefore, the correct answer is **Option D: Aquatic insects**.

### Final Answer:
The ammonotelic animals among the given options are **aquatic insects**.