15. The structure of compound $\mathbf { P }$ is\\
(A) $\mathrm { CH } _ { 3 } \mathrm { CH } _ { 2 } \mathrm { CH } _ { 2 } \mathrm { CH } _ { 2 } - \mathrm { C } \equiv \mathrm { C } - \mathrm { H }$
(B)
(C)\\
\includegraphics[alt={}]{smile-edc3c1924b986062dffc94cfcc3bd304797b4a4c}
(D)\\
\includegraphics[alt={}]{smile-9932ee79aced3a1f0a05b6f475a5abf26b717ce5}
ANSWER: D\\