Absence of thumbs is characteristic of

Options

A. rabbit
B. man
C. frog
D. monkey

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which of the given animals (rabbit, man, frog, monkey) is characterized by the absence of thumbs.

2. **Analyzing Each Option**:
- **Rabbit**: Rabbits have a forelimb structure that includes a thumb, which helps them in digging and grasping.
- **Man**: Humans have a well-developed thumb that allows for a strong grip and manipulation of objects.
- **Monkey**: Monkeys, being primates, also possess thumbs that are opposable, aiding in grasping and climbing.
- **Frog**: Frogs are amphibians and have a different limb structure. They possess webbed feet that assist in swimming and leaping.

3. **Identifying the Key Feature**: The key feature to note here is the presence or absence of thumbs. The frog is noted for having webbed feet with only four digits, indicating the absence of a thumb.

4. **Conclusion**: Based on the analysis, the animal characterized by the absence of thumbs is the **frog**.

### Final Answer:
The absence of thumbs is characteristic of the **frog**.

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