The Average Molecular Translational Kinetic Energy of a Molecule in an Ideal

The average molecular translational kinetic energy of a molecule in an ideal gas is

A) $\frac { 3 } { 2 }$ k_BT.
B) $\frac { 3 } { 2 }$ RT.
C) $\frac { 5 } { 2 }$ k_BT.
D) $\frac { 5 } { 2 }$ RT.
E) $\frac { n + 3 } { 2 }$ k_BT,where n = number of internal degrees of freedom.