Which of the following are envisaged by the Right against Exploitation in the Constitution of India?

Right against Exploitation is covered under Articles 23 and 24 of the Constitution.

1. Prohibition of traffic in human beings and forced labour — Correct. Article 23 prohibits trafficking, begar and other forms of forced labour.
2. Abolition of untouchability — Incorrect. This is under Article 17, part of the Right to Equality, not Right against Exploitation.
3. Protection of the interests of minorities — Incorrect. This belongs to Cultural and Educational Rights (Articles 29–30).
4. Prohibition of employment of children in factories and mines — Correct. Article 24 prohibits employment of children below 14 years in factories, mines and hazardous occupations.

Hence, 1 and 4 only are correct.