Sensory epithelial cells are modified

Options

A. Nerve cells
B. Columnar cells
C. Glandular cells
D. None of these.

Answer

### Step-by-Step Text Solution:

1. **Understanding Sensory Epithelial Cells**: Sensory epithelial cells are specialized cells that form the sensory epithelium. This layer of tissue is responsible for detecting and collecting signals from the environment.

2. **Role of Sensory Epithelium**: The primary function of the sensory epithelium is to receive sensory stimuli, which can include light, sound, taste, and touch. This is crucial for the organism's interaction with its environment.

3. **Modification of Sensory Epithelial Cells**: These sensory epithelial cells are modified into a specific type of cell known as columnar cells. Columnar cells are characterized by their elongated shape and are specialized for sensory reception.

4. **Identifying the Correct Answer**: In the context of the question, the modification of sensory epithelial cells leads to the formation of columnar cells. Therefore, the correct answer to the question is option B, which states that sensory epithelial cells are modified by columnar cells.

5. **Eliminating Incorrect Options**: Other options such as nerve cells, glandular cells, and "none of these" are not correct in this context. Sensory epithelial cells are specifically modified into columnar cells, making option B the only correct choice.