In a monohybrid cross, we study ..........character.

Answer

**Step-by-Step Solution:**

1. **Understanding Monohybrid Cross**: A monohybrid cross is a genetic cross that examines the inheritance of a single trait or character. It involves two individuals that differ in one specific trait.

2. **Identifying the Character Studied**: In a monohybrid cross, we focus on one character or trait. This means we are looking at how this single trait is passed from parents to offspring.

3. **Contrast with Dihybrid Cross**: It is important to note that in a dihybrid cross, we study two characters simultaneously. However, in a monohybrid cross, the focus is strictly on one character.

4. **Conclusion**: Therefore, in a monohybrid cross, we study **one** character.

**Final Answer**: In a monohybrid cross, we study **one** character.

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