$6 \cdot 5(-1)^{2^{3^{5}}}+(-1)^{5^{3^{2}}}$ equals
(A) 2.
(B) 1.
(C) 0.
(D) -2.
(2nd "Five Sheep Cup" Junior High School Mathematics Competition, 1990)
[Solution] Since $m=2^{3^{3^{5}}}$ is even and $n=5^{3^{2}}$ is odd, then
$$
(-1)^{m}+(-1)^{n}=0 \text {. }
$$

Therefore, the correct choice is $(C)$.