Identify the final product of the following reaction sequence:
$o$-Phthalaldehyde $\xrightarrow{\text{OH}^-} A$ $\xrightarrow{\text{H}^+, \Delta} ?$

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:

Consider the above reaction sequence and identify the product $B$.

In the following sequence of reactions,the final product $D$ is:

During the reaction of benzaldehyde with alkali,one of the products is:

Consider the following sequence of reactions.
$1$-methylindene $\xrightarrow[NaHSO_3]{OsO_4} A$ $\xrightarrow[2. NaOH, \text{heat}]{1. HIO_4} B$
The final product $(B)$ is