Concept:The parts must form a logical sequence between the given opening and closing sentences, moving from advantages to a drawback and then to a related form of communication.
Explanation:Sentence 1 says email has changed communication.
Part P explains its speed advantage over letters. This directly follows sentence 1.
Part R adds another benefit: file sharing and formal contact. So R comes after P.
Part S introduces a drawback with "However" — emails lack personal touch. This logically follows the benefits.
Part Q then shifts to instant messaging, which is also popular. This fits before the closing sentence 6 about choosing the right medium.
Thus, the correct order is P, R, S, Q.
Answer:Option A: PRSQ