The membranous cover of the ovum at ovulation is

Options

A. Corona radiata
B. Zona radiata
C. Zona pellucida
D. Chorion

Explanation

To solve the question regarding the membranous cover of the ovum at ovulation, we will analyze the options provided and identify the correct answer step by step.

### Step-by-Step Solution:

1. **Understanding the Structure of the Ovum**:
- The ovum (egg cell) has protective layers surrounding it. These layers are essential for its protection and function during fertilization.

2. **Identifying the Layers**:
- There are two main layers surrounding the ovum:
- **Corona Radiata**: This is the outer layer, which consists of follicular cells that provide nourishment to the ovum.
- **Zona Pellucida**: This is the inner layer, which is a thick, transparent membrane composed of glycoproteins.

3. **Analyzing the Options**:
- **Option 1: Corona Radiata**: This is the outermost layer surrounding the ovum.
- **Option 2: Zona Radiata**: This term is often used interchangeably with zona pellucida in mammals.
- **Option 3: Zona Pellucida**: This is the inner layer, not the outer layer.
- **Option 4: Boreum**: This is not a recognized term related to the layers of the ovum.

4. **Conclusion**:
- Since the question specifically asks for the membranous cover at ovulation, the correct answer is **Corona Radiata**. It is the outer layer that is present during ovulation.

### Final Answer:
The membranous cover of the ovum at ovulation is **Corona Radiata**.

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