Aldol condensation will not be observed in

Correct order for nucleophilic addition reaction :
$(1)$ $C_{6}H_{5}COC_{6}H_{5}$
$(2)$ $C_{6}H_{5}CHO$
$(3)$ $p-CH_{3}C_{6}H_{4}CHO$
$(4)$ $p-CH_{3}OC_{6}H_{4}CHO$

Comment on the stereochemistry of the products for the following reaction:
$3$-methylpentan-$2$-one + $CH_3MgBr$ followed by $NH_4Cl$ workup.

$PhMgBr$ [Excess] + $CH_3COCl \xrightarrow{H_3O^+}$
The final product of the above reaction is:

Which of the following products is formed when benzaldehyde is treated with $CH_3MgBr$ and the addition product so obtained is subjected to acid hydrolysis?

What are $A, B, C$ and $D$ in the following cross-aldol condensation reaction?
$\text{Propanal} + \text{Ethanal} \xrightarrow[ii) \ \Delta]{i) \ NaOH} A + B + C + D$
(The products are the four possible $\alpha,\beta$-unsaturated aldehydes formed by self and cross-aldol condensation followed by dehydration.)