Cannizzaro reaction between formaldehyde molecules involves the formation of

Given below are two statements:
Statement $I$: Cross aldol condensation between two different aldehydes will always produce four different products.
Statement $II$: When semicarbazide reacts with a mixture of benzaldehyde and acetophenone under optimum pH, it forms a condensation product with acetophenone only.
In the light of the above statements, choose the correct answer from the options given below:

Which of the following is reduced by $Zn-Hg/HCl$ to give the corresponding hydrocarbon?

Which of the following will not give the Cannizzaro reaction?

Product $B$ is :

Which of the following pairs of reactants is most effective in forming an enamine?