$C_7H_6O$ is the molecular formula of $X$,which gives a negative Fehling test but a positive Tollen's test. $X$ $\xrightarrow[AcONa]{Ac_2O} Y$ $\xrightarrow[Me_2NH]{1. SOCl_2} Z$. The correct option is:

• A
  $X$ to $Y$ is called Claisen condensation
• B
  $Y$ is $Ph-CH=CH-COOH$
• C
  $Z$ is $Ph-CH=CH-CONMe_2$
• D
  $X$ is $Ph-CHO$