If $P$ is a negative integer, which of the following is always positive?
(A) $P^{2}$
(B) $\frac{1}{P}$
(C) $2 P$
(D) $P-1$
(E) $P^{3}$
If $P$ is a negative integer, which of the following is always positive?
(A) $P^{2}$
(B) $\frac{1}{P}$
(C) $2 P$
(D) $P-1$
(E) $P^{3}$

## Solution

If we try $P=-1$,
(A) $P^{2}=1$
(B) $\frac{1}{P}=-1$
(C) $2 P=-2$
(D) $P-1=-2$
(E) $P^{3}=-1$

and so the only possibility for the correct answer is (A). (In fact, $P^{2}$ is always greater than or equal to 0 , regardless of the choice for $P$.)