Three closed vessels A,B and C are at the same temperature T and contains gases which obey the Mawellian distribution of velocities. Vessel A containe only `O_(2)`. B only `N_(2)` and C a mixture of equal quantities of `O_(2)` and `N_(2)`. If the average speed of the `O_(2)` molecules in vessel A is `V_(1)`, that of the `N_(2)` molecule in vessel C is:
A. `((V_(1)+V_(2)))/(2)`
B. `V_(1)`
C. `(V_(1)+V_(2))^(1//2)`
D. `sqrt(3kT//M)`