Tap roots are common in

Options

A. monocots
B. dicots
C. weeds
D. grasses

Answer

### Step-by-Step Solution:

1. **Understanding Tap Roots**: Tap roots are the primary roots that grow directly downward and are typically thicker than other roots. They can branch into secondary and tertiary roots.

2. **Identifying Plant Groups**: In the context of flowering plants, they are classified into two main groups based on the number of cotyledons in their seeds: monocots (one cotyledon) and dicots (two cotyledons).

3. **Characteristics of Dicots**: Dicots are known to have a tap root system. The tap root develops from the radical of the seed and is characterized by a strong primary root that can further branch out into secondary and tertiary roots.

4. **Examples of Tap Root Plants**: Common examples of dicots with tap roots include plants like carrots, which have tap roots modified for storage, helping the plant survive in unfavorable conditions.

5. **Classification of Tap Roots**: Tap roots can be classified based on their shape into three types:
- Conical (e.g., carrot)
- Fusiform (widest in the middle, tapering at both ends)
- Napiform (bulbous shape)

6. **Conclusion**: Based on the characteristics and examples discussed, tap roots are commonly found in dicots.

### Final Answer:
Tap roots are common in **dicots** (Option B).

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