Đáp án đúng: C
Giải chi tiết:Đáp án C
\(\begin{gathered} TN1:{C_2}{H_5}OH\xrightarrow{{{H_2}S{O_4},{{170}^0}C}}{C_2}{H_4} + {H_2}O \hfill \\ \,\,\,\,\,\,\,\,\,\,\,\,0,2\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, \leftarrow 0,2mol \hfill \\ TN2:\,2{C_2}{H_5}OH\xrightarrow{{{H_2}S{O_4},{{170}^0}C}}{({C_2}{H_5})_2}O + {H_2}O \hfill \\ \,\,\,\,\,\,\,\,\,\,\,\,\,0,2 \to \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,0,1\, \Rightarrow \,\,m({\text{ete}}) = 7,4. \hfill \\ \end{gathered} \)