question_answer

Increasing order of reactivity of the following compounds for \[{{S}_{N}}1\] substitution is:
[a]	[b]
[c]	[d]

A) [a] < [b] < [d] <[c]       

B) [b] < [c] < [d] < [a]

C) [b] < [c] < [a] < [d]      

D) [b] < [a] < [d] < [c]

Correct Answer: D

Solution :

Official answer is\[\to 4\](for NTA)

\[Fact\to stability\text{ }of\text{ }carbocation\propto Rate\text{ }of\text{ }S{{N}^{2}}.\]