An alcohol, $X$, and a dicarboxylic acid, $Y$, react to produce the double ester, $Z$. The diagram displays the structure of the ester. Which row concerning the reactants that form ester $Z$ is correct?
- Asecondary; non-planar
- Bsecondary; planar
- Ctertiary; non-planar
- Dtertiary; planar