The ciliated columnar epithelial cells in humans are known to occur in
(a) Fallopian tubes and urethra
(b) Eustachian tube and stomach lining
(c) Bronchioles and Fallopian tubes
(d) Bile duct and oesophagus

Options

A. Fallopian tubes and urethra
B. Eustachian tube and stomach lining
C. Bronchioles and Fallopian tubes
D. Bile duct and oesophagus

Answer

To determine where ciliated columnar epithelial cells are found in humans, we can analyze the options provided in the question step by step.

### Step 1: Understand the Characteristics of Ciliated Columnar Epithelium
Ciliated columnar epithelial cells are tall, column-like cells that have cilia on their surface. These cilia help in the movement of substances across the epithelial surface, which is crucial in certain organs.

**Hint:** Remember that ciliated columnar epithelium is primarily involved in moving substances, so think about where this function is important in the body.

### Step 2: Analyze Each Option
- **Option (a): Fallopian tubes and urethra**
- The fallopian tubes are lined with ciliated columnar epithelium to help transport the ovum. However, the urethra is not typically lined with ciliated columnar epithelium; it has a different type of epithelium.

- **Option (b): Eustachian tube and stomach lining**
- The Eustachian tube does have ciliated epithelium, but the stomach lining is lined with simple columnar epithelium, not ciliated columnar epithelium.

- **Option (c): Bronchioles and Fallopian tubes**
- Both bronchioles and fallopian tubes are lined with ciliated columnar epithelium. The cilia in bronchioles help move mucus and trapped particles out of the respiratory tract, while in the fallopian tubes, they help move the ovum.

- **Option (d): Bile duct and oesophagus**
- The bile duct does not have ciliated columnar epithelium; it is lined with simple cuboidal epithelium. The oesophagus is lined with stratified squamous epithelium.

### Step 3: Conclusion
After analyzing all options, the correct answer is **(c) Bronchioles and Fallopian tubes**, as both structures are known to contain ciliated columnar epithelial cells.

**Final Answer:** (c) Bronchioles and Fallopian tubes