_________ isdirectly connected to the outer nuclear membrane.

Options

A. Mitochondria
B. Golgi body
C. ER
D. Chloroplast

Explanation

To answer the question "_________ is directly connected to the outer nuclear membrane," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Structure of the Nucleus**: The nucleus is surrounded by two membranes known as the inner nuclear membrane and the outer nuclear membrane.

2. **Identifying the Connection**: The outer nuclear membrane is not isolated; it has connections to other cellular structures.

3. **Recognizing the Endoplasmic Reticulum (ER)**: The outer nuclear membrane is continuous with the endoplasmic reticulum (ER). This means that the outer nuclear membrane and the ER are physically connected.

4. **Explaining the Lumen Connection**: The space between the inner and outer nuclear membranes is directly connected to the lumen of the endoplasmic reticulum, indicating that they share a direct pathway.

5. **Choosing the Correct Answer**: Given the options provided (mitochondria, Golgi body, ER, chloroplast), the correct answer is the endoplasmic reticulum (ER), as it is the structure that is directly connected to the outer nuclear membrane.

### Final Answer:
**Endoplasmic Reticulum (ER)** is directly connected to the outer nuclear membrane.

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