1. Given $a=3^{55}, b=4^{44}, c=5^{33}$, then ( ).
(A) $a<b<c$
(B) $c<b<a$
(C) $c<a<b$
(D) $a<c<b$
\begin{array}{l}-1 . \text { (C). } \\ \because a=3^{55}=\left(3^{5}\right)^{11}=243^{11}, \\ b=4^{44}=\left(4^{4}\right)^{11}=256^{11}, \\ c=5^{33}=\left(5^{3}\right)^{11}=125^{11}, \\ \therefore c<a<b, \text { choose (C). }\end{array}