[单选题]
A sample of an ideal gas is heated and its Kepohw2:9 mm.tokfj:r 2lvin temperature duu,z;qcjf 9zqx n 9o+lm( 0lud8a :w5+1wma vcoubles. What happens to the average speed of thn w 9+cu8:qv xdql9aa1f z low0 j+,uu(m5;mcze molecules in the sample?
A. It does not change.
B. It doubles.
C. It halves.
D. none of the above
