Secondary and tertiary alcohols always gives E 1 reaction in dehydration. Primary…

Secondary and tertiary alcohols always gives E₁
reaction in dehydration. Primary, alcohols whose β-carbon is 3^oor 4^o also give E₁ reaction. However, the primary alcohols whose β-carbon is 1^oor 2^o give E₂ reaction. Dehydrating agents like conc. H₂SO₄, Al₂O₃, anhydrous ZnCl₂ are used.
The reactivity of alcohols for elimination reaction lies in following sequence:
Tertiary alcohol > secondary alcohol > primary alcohol
Electron attracting groups present in alcohols decrease the reactivity for dehydration. Greater is the –I effect of the group present in alcohol, less will be its reactivity. Both E₁ and E₂ mechanism give the product according to Saytzeff’s rule, i.e., major product is the most substituted alkene
\[\text { 3-Methyl butan-2-ol }\] 

Answer the following questions:
Arrange the reactivity of given four alcohols in decreasing order of dehydration.
\[\begin{array}{l} \\ \text { (A) } \end{array}\] 
\[\begin{array}{l} \\ \text { (B) } \end{array}\] 
\[\begin{array}{l} \\ \text { (C) } \end{array}\] 
\[\begin{array}{l} \\ \text { (D) } \end{array}\]