Concept:
CDSCO stands for Central Drugs Standard Control Organization. It is the national regulatory authority for drugs in India.
Step 1: Main responsibility of CDSCO.
CDSCO is responsible for approval of new drugs, regulation of clinical trials, and control of drug standards at the central level.
Step 2: Drug approval.
New drugs require regulatory approval before marketing. CDSCO plays a key role in this process.
Step 3: Drug regulation.
CDSCO also helps regulate import, quality, and safety of drugs and medical products.
Step 4: Why other options are wrong.
Drug price fixation is done by NPPA.
Pharmacy education is regulated by PCI.
Pharmacist registration is handled by State Pharmacy Councils.
Step 5: Final answer.
Thus, CDSCO is responsible for drug approval and regulation.
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\boxed{\text{Drug approval and regulation}}
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