Which of the Following Molecular Formulas Is Consistent with the Formula

Which of the following molecular formulas is consistent with the formula for a molecule containing one alkyne and no other degrees of unsaturation? $$\begin{array} { c c c l } \mathrm { C } _ { 10 } \mathrm { H } _ { 20 } & \mathrm { C } _ { 10 } \mathrm { H } _ { 22 } & \mathrm { C } _ { 10 } \mathrm { H } _ { 18 } & \mathrm { C } _ { 10 } \mathrm { H } _ { 19 } \\\text { I } & \text { II } & \text { III } & \text { IV }\end{array}$$

A) I
B) II
C) III
D) IV