Both male and female pigeons secrete milk through

Options

A. salivary glands
B. modified sweat glands
C. crop
D. gizzard

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks where both male and female pigeons secrete milk from. This refers to a unique feature of pigeons, which is the production of a substance often referred to as "pigeon milk."

2. **Identifying the Source of Pigeon Milk**: Pigeon milk is not milk in the traditional sense but a secretion that is produced in a specific part of the pigeon's anatomy. It is important to identify the correct anatomical structure responsible for this secretion.

3. **Locating the Crop**: The crop is a part of the digestive system in birds, including pigeons. It is an expanded, muscular pouch located at the lower end of the esophagus. The crop serves as a storage area for food before it moves into the gizzard for digestion.

4. **Understanding the Crop's Function**: In pigeons, the epithelial lining of the crop undergoes a process where it degenerates to produce a nutrient-rich secretion. This secretion is what is referred to as pigeon milk.

5. **Composition of Pigeon Milk**: Pigeon milk contains water, fats, proteins, lactose, and immune boosters, making it highly nutritious for the hatchlings. This is crucial for the survival and growth of the young pigeons.

6. **Conclusion**: Based on the anatomical structure and the process of secretion, the correct answer to the question is that both male and female pigeons secrete milk through the **crop**.

### Final Answer:
Both male and female pigeons secrete milk through the **crop**.

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