A' is one amembranous spherical body present in one double membrane bound cell organelle.
'B' is another a membranous organelle present upon another single membrane bound cell organelle. A & B are respectively .

Options

A. 80 S and 70 S ribosomes
B. Nucleus and 70 S ribosomes
C. 70 S ribosomes and Nucleolus
D. Nucleolus and 80 S ribosomes

Answer

To solve the question, we need to identify the two components 'A' and 'B' based on the descriptions provided.

### Step-by-Step Solution:

1. **Identify 'A':**
- The question states that 'A' is a membranous spherical body present in a double membrane-bound cell organelle.
- The only double membrane-bound organelle in eukaryotic cells is the nucleus.
- Within the nucleus, there is a dense spherical structure known as the nucleolus.
- Therefore, 'A' is identified as the **Nucleolus**.

2. **Identify 'B':**
- The question describes 'B' as another membranous organelle present on a single membrane-bound cell organelle.
- The endoplasmic reticulum (ER) is a single membrane-bound organelle, and ribosomes are often found attached to the rough endoplasmic reticulum.
- Therefore, 'B' is identified as **Ribosomes**.

3. **Conclusion:**
- Based on the analysis, 'A' is the **Nucleolus** and 'B' is **Ribosomes**.

### Final Answer:
- A is **Nucleolus** and B is **Ribosomes**.

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