Which of the following is a mismatched pair?

Options

A. `{:("Endocrine gland"," Hormone"),("Pituitary"," ACTH"):}`
B. `{:("Endocrine gland"," Hormone"),(" Testes "," Testosterone "):}`
C. `{:("Endocrine gland"," Hormone"),("Pancreas "," Calcitonin "):}`
D. `{:("Endocrine gland"," Hormone"),("Pineal gland "," Melatonin "):}`

Explanation

To determine which of the following pairs is mismatched, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Identify the Glands and Their Hormones:**
- We have several endocrine glands and the hormones they secrete. We need to check if the hormone listed corresponds correctly to the gland mentioned.

2. **Evaluate Each Option:**
- **Option A: Pituitary Gland - ACTH**
- The pituitary gland secretes ACTH (Adrenocorticotropic Hormone), which is correct.
- **Option B: Testes - Testosterone**
- The testes secrete testosterone, which is also correct.
- **Option C: Pancreas - Calcitonin**
- The pancreas primarily secretes insulin and glucagon. Calcitonin is actually secreted by the thyroid gland. This pair is incorrect.
- **Option D: Pineal Gland - Melatonin**
- The pineal gland secretes melatonin, which is correct.

3. **Conclusion:**
- The mismatched pair is **Option C: Pancreas - Calcitonin** since calcitonin is not secreted by the pancreas but by the thyroid gland.

### Final Answer:
The mismatched pair is **C: Pancreas - Calcitonin**.

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