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Answer 1

The key word is all.

Every store managed by $M$ must satisfy at least one of the two allowed conditions.

Therefore, the outer structure must be:

$\forall S$ and the condition applies only when

$S.\mathrm{MANAGER}=M.\mathrm{NAME}$.

This gives,

$(S\in \mathrm{Stores}\land S.\mathrm{MANAGER}=M.\mathrm{NAME})\Rightarrow(\mathrm{NailSale}(S)\lor \mathrm{PowerSale}(S))$

Inside $\mathrm{NailSale}$ and $\mathrm{PowerSale}$, existential tuple variables are used because the query requires the existence of an appropriate sale/product tuple.

So the quantifier pattern is conceptually:

$\forall \mathrm{Store}$

followed by

$\exists \mathrm{Sale},\exists \mathrm{Product}$

inside each permitted alternative.

B requires only one qualifying store.

C incorrectly requires every managed store to satisfy both conditions.

D imposes the sales condition on every store in the database, including stores not managed by $M$.

Therefore,

Answer : $\boxed{\mathrm{A}}$