MCQ
Which of the following is $2$ -carboxy ethyl ?
- A$-CH_2-COOH$
- B$\begin{array}{*{20}{c}}
{ - C{H_2} - C{H_2}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,CHO}
\end{array}$ - C$\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,O} \\
{\,\,\,\,\,\,\,\,\,\,||} \\
{ - C{H_2} - C - H}
\end{array}$ - ✓$-CH_2-CH_2-COOH$
