The plant which is used for studying hybrid vigour or heterosis is

Options

A. maize
B. pea
C. datura
D. none of these

Answer

### Step-by-Step Solution:

1. **Understand the Concept of Hybrid Vigor (Heterosis)**:
- Hybrid vigor, also known as heterosis, refers to the phenomenon where the offspring (hybrids) exhibit superior qualities compared to their parents. This can include increased growth rate, higher yield, improved fertility, and better resistance to diseases.

2. **Identify the Plants Used for Studying Hybrid Vigor**:
- Various plants can exhibit hybrid vigor, but some are more commonly studied than others. The question asks specifically for the plant used to study this phenomenon.

3. **Evaluate the Options Given**:
- The options provided are:
- A) Maize
- B) Pea
- C) Datura
- D) None of these
- Among these, we need to identify which plant is primarily associated with the study of hybrid vigor.

4. **Recall Historical Context**:
- Maize (corn) has been widely researched in the context of hybrid vigor. It was one of the first crops where hybridization techniques were applied, leading to significant advancements in agricultural productivity.

5. **Select the Correct Answer**:
- Based on the understanding and historical context, the correct answer to the question is **Option A: Maize**.

### Final Answer:
The plant which is used for studying hybrid vigor or heterosis is **Maize (Option A)**.

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