**Core Concept**
The Narcotic Drugs and Psychotropic Substances (NDPS) Act is a law in India that regulates the use, production, and distribution of narcotic drugs and psychotropic substances. This law aims to prevent the misuse of these substances and to provide for their proper use in medical and scientific research.

**Why the Correct Answer is Right**
The NDPS Act was enacted in 1985, replacing the earlier Narcotic Drugs and Psychotropic Substances Act of 1980. This law has undergone several amendments to keep pace with the changing global scenario and to strengthen the provisions for prevention of drug abuse. The Act prohibits the manufacture, sale, and possession of narcotic drugs and psychotropic substances, except for medical and scientific purposes.

**Why Each Wrong Option is Incorrect**
**Option A:** 1950 - This is incorrect because the NDPS Act was not passed in 1950. The Indian Constitution was adopted in 1950, but the NDPS Act was enacted much later.
**Option B:** 1960 - This is incorrect because the NDPS Act was not passed in 1960. This decade saw the introduction of several social and economic reforms in India, but the NDPS Act was not enacted during this time.
**Option C:** 1970 - This is incorrect because the NDPS Act was not passed in 1970. This decade saw significant economic and social changes in India, but the NDPS Act was not enacted during this time.

**Clinical Pearl / High-Yield Fact**
It is essential to note that the NDPS Act has undergone several amendments to keep pace with the changing global scenario and to strengthen the provisions for prevention of drug abuse.

**Correct Answer: C. 1985**