Q49. Identify ' $A$ ' in the following reaction:\\
\includegraphics[max width=\textwidth, alt={}, center]{4ed921fa-68a7-49bb-8423-eac8cce8175f-09_215_1216_1181_171}
(1)\\
\includegraphics[alt={}]{smile-c730bc9797ec30c16ffa183f4f21bd453e9c9e65}
(2)\\
\includegraphics[alt={}]{smile-a80237d72341d4340ddaa90116e3394e66370733}
(3)\\
\includegraphics[alt={}]{smile-6e88c56b302a2cf18341d4c2ec9ade3a7fd50b97}
(4)\\
\includegraphics[alt={}]{smile-905826f8f925f62fe477127927f3264d88c7673f}