Which type of isomerism is shown by $1-\mathrm{B}\mathrm{u}\mathrm{t}\mathrm{e}\mathrm{n}\mathrm{e}$ and $\mathrm{c}\mathrm{y}\mathrm{c}\mathrm{l}\mathrm{o}\mathrm{b}\mathrm{u}\mathrm{t}\mathrm{a}\mathrm{n}\mathrm{e}$ ? 

Given,



Which of the given compounds can exhibit tautomerism?

Assertion A : Enol form of acetone $\left[{\mathrm{CH}}_3{\mathrm{COCH}}_3\right]$ exists in $<0.1\%$ quantity. However, the enol form of acetyl acetone $\left[{\mathrm{CH}}_3{\mathrm{COCH}}_2{\mathrm{OCCH}}_3\right]$ exists in approximately $15\%$quantity.

Reason R : enol form of acetyl acetone is stabilized by intramolecular hydrogen bonding, which is not possible in enol form of acetone.

Choose the correct statement:

Which of the following carbonyl compounds will exhibit enolization?

(i) 

(ii)

(iii) 

(iv) 

(v) 

Compounds $\mathrm{A}$ and $\mathrm{C}$ in the following reaction are

The following compounds

are