Read the following statements and find the number of CORRECT statements.
P. Cancerous cells compete with normal cells for nutrients.
Q. With repeated use of drugs, the tolerance level of the receptors present in our body increases.
R. Cocaine enhances the action of the neurotransmitter dopamine.
S. Cannabinoids are abused by sportspersons.

Options

A. One
B. Two
C. Three
D. Four

Answer

To determine the number of correct statements from the given options, let's analyze each statement one by one:

### Step 1: Analyze Statement P
**Statement P:** "Cancerous cells compete with normal cells for nutrients."
- **Analysis:** This statement is correct. Cancerous cells are characterized by uncontrolled growth and they require nutrients to sustain their rapid division. They compete with normal cells for these nutrients.

### Step 2: Analyze Statement Q
**Statement Q:** "With repeated use of drugs, the tolerance level of the receptors present in our body increases."
- **Analysis:** This statement is incorrect. With repeated use of drugs, the body often becomes tolerant to the effects of the drug, which means that the receptors may become less responsive, not more. Therefore, the tolerance level of receptors generally decreases with continuous drug use.

### Step 3: Analyze Statement R
**Statement R:** "Cocaine enhances the action of the neurotransmitter dopamine."
- **Analysis:** This statement is correct. Cocaine works by blocking the reuptake of dopamine in the brain, which leads to an increase in dopamine levels in the synaptic cleft, enhancing its action.

### Step 4: Analyze Statement S
**Statement S:** "Cannabinoids are abused by sportspersons."
- **Analysis:** This statement is also correct. Cannabinoids can be used for pain relief and may enhance endurance, which is why they are sometimes abused by athletes. However, they are banned substances in many sports.

### Conclusion
Now, let's summarize the correctness of each statement:
- Statement P: Correct
- Statement Q: Incorrect
- Statement R: Correct
- Statement S: Correct

**Total Correct Statements:** 3 (P, R, and S are correct)

### Final Answer
The number of correct statements is **3**.

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