Step 1: Concept
The Narcotic Drugs and Psychotropic Substances (NDPS) Act defines penalties based on the quantity of the prohibited substance involved: small, intermediate, or commercial.
Step 2: Meaning
Intermediate quantity refers to any amount that falls between the government-specified "small" and "commercial" limits.
Step 3: Analysis
For commercial quantities, the punishment is 10–20 years. However, for intermediate quantities (greater than small but less than commercial), the law prescribes rigorous imprisonment for a term which may extend to 10 years and a fine up to 1 lakh rupees.
Step 4: Conclusion
Thus, option A represents the correct legal penalty for intermediate quantities.
Final Answer: (A)