1. In the arithmetic sequence $\left\{a_{n}\right\}$, if $a_{4}+a_{6}+a_{8}+a_{10}+$ $a_{12}=120$, then the value of $2 a_{9}-a_{10}$ is ( ).
(A) 20
(B) 22
(C) 24
(D) 28
\begin{array}{l}-1 .(\mathrm{C}) \\ \because a_{4}+a_{6}+a_{8}+a_{10}+a_{12} \\ =5 a_{1}+(3+5+7+9+11) d \\ =5\left(a_{1}+7 d\right)=120 \Rightarrow a_{1}+7 d=24, \\ \therefore 2 a_{9}-a_{10}=2\left(a_{1}+8 d\right)-\left(a_{1}+9 d\right) \\ =a_{1}+7 d=24 .\end{array}