In the equations below, the letters W, X, Y and Z each stand for whole numbers. Once the equation is correctly balanced, which equation shows that one of W, X, Y or Z has to be 5?
- A$\text{W C}_3\text{H}_7\text{COOH} + X\text{O}_2 \rightarrow Y\text{CO}_2 + Z\text{H}_2\text{O}$
- B$\text{W C}_4\text{H}_8 + X\text{O}_2 \rightarrow Y\text{CO}_2 + Z\text{H}_2\text{O}$
- C$\text{W H}_3\text{PO}_4 + X\text{NaOH} \rightarrow Y\text{Na}_2\text{HPO}_4 + Z\text{H}_2\text{O}$
- D$\text{W NH}_3 + X\text{O}_2 \rightarrow Y\text{N}_2 + Z\text{H}_2\text{O}$