A sensory neuron enters the spinal cord from the :

Options

A. anterior root
B. posterior root
C. lateral horn
D. superior root

Explanation

To answer the question "A sensory neuron enters the spinal cord from the:", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Role of Sensory Neurons**:
- Sensory neurons are responsible for transmitting sensory information from the body to the central nervous system (CNS), which includes the brain and spinal cord.

2. **Identify the Pathway of Sensory Neurons**:
- Sensory neurons have a specific pathway they follow to reach the spinal cord. They carry signals from sensory receptors (like skin, eyes, ears) to the spinal cord.

3. **Know the Structure of the Spinal Cord**:
- The spinal cord has specific roots through which different types of neurons enter and exit. The two main roots are the dorsal (posterior) root and the ventral (anterior) root.

4. **Differentiate Between Dorsal and Ventral Roots**:
- The dorsal root (also known as the posterior root) carries sensory information into the spinal cord, while the ventral root (anterior root) carries motor information out of the spinal cord.

5. **Conclude the Correct Answer**:
- Since sensory neurons enter the spinal cord through the dorsal root, which is synonymous with the posterior root, the correct answer to the question is the **posterior root**.

### Final Answer:
A sensory neuron enters the spinal cord from the **posterior root**.

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