Counting determinants

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Q. Consider the set $\mathbb A$ of all determinants of order $3$ with entries $0$ or $1$ only. Let $\mathbb B$ be the subset of $\mathbb A$ consisting of all determinants with value $1$ and $\mathbb C$ be the subset of $\mathbb A$ of all the determinants with value $-1$. Choose the correct option:

$(a)$ $\mathbb C$ is empty.

$(b)$ $\mathbb B$ has as many elements as $\mathbb C$

$(c)$ $\mathbb {A=B \cup C}$

$(d)$ $\mathbb B$ has twice as many elements as $\mathbb C$

One way could be to list down all the determinants and count, which is the only thing I could think of. But what if instead of order $3$ we have order $n$?

Also, what is a general way to tackle such problems?