These positive effects vary from genetic changes that

• Ordering of Words

These positive effects vary from genetic changes that

• P: to other related infections,
• Q: make us more resistant to the diseases responsible
• R: for epidemics and
• S: which have effects on human that are

hard to pin down and quantify.

1. QRPS
2. SQPR
3. PRSQ
4. RPQS

Answer

These positive effects vary from genetic changes that make us more resistant to the diseases responsible for epidemics and to other related infections, which have effects on human that are hard to pin down and quantify.

The correct option is A.