Correct option is (b)
Order of stability of carbocations is
primary < secondary < tertiary
Dehydration of primary alcohol gives primary carbocation, and dehydration of secondary, tertiary alcohol gives secondary and tertiary carbocation respectively.
A is primary alcohol C and D are secondary alcohol.
B is tertiary alcohol, hence on dehydration, it will give tertiary carbocation which will be more stable than others.
Hence, option B is correct.