Propane,C₃H₈,is Flammable and Used in Rural Areas Where Natural Gas

Propane,C₃H₈,is flammable and used in rural areas where natural gas is not available.What is the coefficient of oxygen in the balanced equation for the combustion of propane? __C₃H₈(g) + __O₂(g) __CO₂(g) + __H₂O(g)

A) 1
B) 5
C) 7
D) 10
E) none of the above