Calculate the work done during the reaction represented by the following thermochemical equation at 300K:

CH₄ + 2O₂ → CO₂ + 2H₂O
(g) (g) (g) (l)

(R = 8.314JK⁻¹mol⁻¹)

a. +4.988kJ
b. -49.88kJ
c. +49.88kJ
d. -4.988kJ