Assertion :- Endocrine glands are called glands of internal secretion.
Reason:- They are ductless and release their hormones in the blood.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "Endocrine glands are called glands of internal secretion." This is true because endocrine glands are responsible for producing hormones that are released directly into the bloodstream, which is why they are referred to as internal secretion glands.

2. **Understanding the Reason**: The reason provided is "They are ductless and release their hormones in the blood." This is also true. Endocrine glands do not have ducts; instead, they secrete hormones directly into the bloodstream, allowing these hormones to travel to various target organs throughout the body.

3. **Connecting Assertion and Reason**: The reason explains the assertion. Since endocrine glands are ductless and release hormones into the blood, this characteristic is what qualifies them as glands of internal secretion. Therefore, the reason supports the assertion effectively.

4. **Conclusion**: Both the assertion and the reason are true, and the reason provides a correct explanation for the assertion. Thus, the correct answer is that both A (Assertion) and R (Reason) are true, and R is the correct explanation of A.

**Final Answer**: Both A and R are true, and R is the correct explanation of A.

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