Which enol form of ethyl 3-oxobutanoate is predominant at equilibrium?

• A. <a href="https://www.sanfoundry.com/wp-content/uploads/2018/08/organic-chemistry-questions-answers-enolates-q6a.png"><img alt="Enol form of ethyl 3-oxobutanoate is predominant at equilibrium - option a" class="alignnone size-full wp-image-224659" height="69" src="https://www.sanfoundry.com/wp-content/uploads/2018/08/organic-chemistry-questions-answers-enolates-q6a.png" width="143"/></a>
• B. <a href="https://www.sanfoundry.com/wp-content/uploads/2018/08/organic-chemistry-questions-answers-enolates-q6b.png"><img alt="Enol form of ethyl 3-oxobutanoate is predominant at equilibrium - option b" class="alignnone size-full wp-image-224660" height="69" src="https://www.sanfoundry.com/wp-content/uploads/2018/08/organic-chemistry-questions-answers-enolates-q6b.png" width="133"/></a>
• C. <a href="https://www.sanfoundry.com/wp-content/uploads/2018/08/organic-chemistry-questions-answers-enolates-q6c.png"><img alt="Enol form of ethyl 3-oxobutanoate is predominant at equilibrium - option c" class="alignnone size-full wp-image-224661" height="70" src="https://www.sanfoundry.com/wp-content/uploads/2018/08/organic-chemistry-questions-answers-enolates-q6c.png" width="143"/></a>
• D. <a href="https://www.sanfoundry.com/wp-content/uploads/2018/08/organic-chemistry-questions-answers-enolates-q6d.png"><img alt="Enol form of ethyl 3-oxobutanoate is predominant at equilibrium - option d" class="alignnone size-full wp-image-224662" height="67" src="https://www.sanfoundry.com/wp-content/uploads/2018/08/organic-chemistry-questions-answers-enolates-q6d.png" width="132"/></a>