Find the correct statement

Options

A. 'Smack' is derived from 'Cannabis sativa.''
B. Now AIDS is completely treatable with anti-retroviral drugs.
C. Bone marrow, thymus and lymph nodes are the primary lymphoid organs.
D. MALT constitutes about 50 percent of lymphoid tissue in human body

Answer

To find the correct statement among the given options, we will analyze each statement one by one.

### Step 1: Analyze the first statement
**Statement:** SMACC is derived from cannabis sativa.
**Analysis:** This statement is incorrect. SMAC (or SMACC) is derived from Papaver somniferum, which is the opium poppy, not cannabis sativa.
**Conclusion:** This statement is wrong.

### Step 2: Analyze the second statement
**Statement:** AIDS is completely treatable with antiretroviral drugs.
**Analysis:** This statement is also incorrect. While antiretroviral drugs can manage AIDS and help individuals live longer, AIDS is not curable.
**Conclusion:** This statement is wrong.

### Step 3: Analyze the third statement
**Statement:** Bone marrow, thymus, and lymph nodes are the primary lymphoid organs.
**Analysis:** This statement is partially incorrect. Bone marrow and thymus are indeed primary lymphoid organs, but lymph nodes are classified as secondary lymphoid organs.
**Conclusion:** This statement is wrong.

### Step 4: Analyze the fourth statement
**Statement:** MALT constitutes about 50% of lymphoid tissue in the human body.
**Analysis:** This statement is correct. MALT (Mucosa-associated lymphoid tissue) does constitute approximately 50% of the lymphoid tissue in the human body.
**Conclusion:** This statement is true.

### Final Answer
The correct statement is: **MALT constitutes about 50% of lymphoid tissue in the human body.**

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