In a thermodynamic process helium gas obeys the law $\frac{\mathrm{T}}{{\mathrm{p}}^{{\displaystyle \raisebox{1ex}{$2$}\!\left/ \!\raisebox{-1ex}{$5$}\right.}}}=\mathrm{constant}$.The heat given to the gas when temperature of m moles of gas is raised from T to 2T is:

• A

  8 RT

• B

  4 RT

• C

  16 RT

• D

  zero