The correct statement about the synthesis of erythritol $(C(CH_2OH)_4)$ used in the preparation of $PETN$ is :

Question

$\begin{array}{1 1}\text{(1) The synthesis requires four aldol condensations between methanol and ethanol.}\\ \text{(2) The synthesis requires two aldol condensations and two Cannizzaro reactions.}\\ \text{(3) The synthesis requires three aldol condensations and one Cannizzaro reaction.}\\ \text{(4) Alpha hydrogens of ethanol and methanol are involved in this reaction.} \end{array} $