P : when
Q : a child develops best
R : like a young plant
S : he is left undisturbed in the same soil

The Proper sequence should be:

A. PQRS

B. QPRS

C. QPSR

D. PQSR

Answer: Option A

Solution(By Examveda Team)

When a child develops best like a young plant he is left undisturbed in the same soil.