You are asked to find the balanced chemical equation for the following reaction :
NH₃ + O₂ --> N₂ + H₂ O

what are the coefficients of NH₃ , O₂ , N₂ , and H₂ O , respectively , in the balanced chemical equation ?
a. 4 , 3 , 2 and 6 respectively
b. 2 , 1.5 , 1 , and 3 respectively
c. 8 , 6 , 4 and 12 respectively
d. 3 , 2 , 4 and 6 respectively