One mode of an ideal monoatomic gas is compressed isothermally in a rigid vessel to double its pressure at room temperature, 27°C. The work done on the gas will be:

The correct option is A
300Rln2
Work done in isothermal process is given as
W=−nRT ln(V2/V1)
W=R × 300 ln(P1/P2)
W=−R × 300 ln(P2/P1)
Since the pressure is doubled, P2 = 2P1
W = -300R ln(2P1/P1) = -300R ln2
Since work is done on the gas, the work done will be positive.
Therefore, W = 300R ln2