Enzymes as they exist inside the cell are

Which of these enzymes are not made of protein?

The following reaction depicts the activity of a particular class of enzymes:
$X-Y$ attached to $C-C$ (Substrate) $\xrightarrow{E}$ $X-Y$ + $C=C$ (Product)
Identify the enzyme class '$E$' from the following options:

Enzymes generally have

Identify $X$ in the figure below.

The enzyme aldolase is an example of which class of enzymes?