Each of the compounds listed below is completely combusted, with one mole of each used. $\text{C}_5\text{H}_{12}\text{O}$, $\text{C}_6\text{H}_{12}$, $\text{C}_6\text{H}_{14}$, $\text{C}_6\text{H}_{14}\text{O}$ How many of these compounds require exactly nine moles of oxygen for complete combustion?
- A1
- B2
- C3
- D4