请选择CBA0r2Z,s0i7y1l5o.r:X7s5{1]+b3bHow old ______ you?:u4M8t3T;E2~*c
A. is:u4M8t3T;E2~*c
B. are:u4M8t3T;E2~*c
C. am:u4M8t3T;E2~*c