Compound $A$ was treated with a large excess of $CH_3MgBr$. The resulting product was exposed to $POCl_3$ /pyridine to give compound $B$,as one of many products.
Which of the following compounds can be $A$ ?

The major product of the following reaction sequence is

The reaction sequence is:
$2-\text{hydroxycyclohexylacetone}$ $\xrightarrow{I_2/NaOH}$ $\xrightarrow{\Delta}$ $\xrightarrow{H^+}$ $\xrightarrow{\Delta} A$
$A$ is:

Which of the following represents the decreasing order of reactivity towards reaction with ammonia?

Assertion: Acetamide has a more polar $C=O$ group than ethyl acetoacetate.
Reason: $-\ddot{N}H_{2}$ is more electron-donating than $-\ddot{O}C_{2}H_{5}$.

What are $\underline{A}, \underline{B}, \underline{C}$ in the following reactions?
$(I)$ $(CH_3 CO_2)_2 Ca \stackrel{\Delta}{\longrightarrow} \underline{A}$
$(II)$ $CH_3 CO_2 H \underset{\text{Red P}}{\stackrel{HI}{\longrightarrow}} \underline{B}$
$(III)$ $2 CH_3 CO_2 H \stackrel{P_4 O_{10}}{\longrightarrow} \underline{C}$
$\underline{A} \quad \underline{B} \quad \underline{C}$