Ammonia Reacts with Oxygen to Form Nitric Oxide and Water $\rarr$

Multiple Choice

Ammonia reacts with oxygen to form nitric oxide and water vapor:
4NH₃ + 5O₂ $\rarr$ 4NO + 6H₂O
When 40.0 g NH₃ and 50.0 g O₂ are allowed to react, which is the limiting reagent

A) NH₃
B) O₂
C) NO
D) H₂O
E) No reagent is limiting.