Fertilised eggs of frog develop into

Options

A. Adult frogs
B. Tadpoles
C. Nymph
D. Both 1 and 2

Explanation

**Step-by-Step Solution:**

1. **Understanding Fertilization in Frogs:**
- Frogs undergo external fertilization, which means that the eggs and sperm are released outside the female's body. This is different from internal fertilization seen in humans.

2. **Development After Fertilization:**
- After fertilization occurs, the fertilized egg does not directly develop into an adult frog. Instead, it first develops into a larval stage known as the tadpole.

3. **Characteristics of Tadpoles:**
- Tadpoles are aquatic and can be herbivorous or omnivorous, differing from adult frogs, which are primarily carnivorous. Tadpoles also have different physiological traits, such as being ammonotelic (excreting ammonia) compared to adult frogs, which are ureotelic (excreting urea).

4. **Stages of Development:**
- The typical developmental sequence is:
- Fertilized egg → Tadpole → Froglet (or baby frog) → Adult frog.
- In some rare cases, fertilized eggs may develop directly into froglets, but this is not common.

5. **Evaluating the Options:**
- The options provided were:
- A) Adult frog
- B) Tadpole
- C) Nymph
- D) Both A and B
- Based on the development process, the correct answer is that the fertilized egg develops into a tadpole.

6. **Conclusion:**
- Therefore, the correct answer to the question "Fertilized eggs of frog develop into" is **Tadpole**.

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