Question

Tautomerism is not exhibited by :

• A.
• B.
• C.
• D.

Answer 1

The correct option is A

Condition for tautomerism : Carbonyl compound having an ⍺-H atom at its $s{p}^3$ hybridised ⍺-C atom.
As option 'a' doesn't have $\alpha$ hydrogen it will not exhibit tautomerism.
All other options will exhibit tautomerism.