Answer: Option (D) is the correct answer.
Explanation:
General formula of an alkyne is [tex]C_{n}H_{2n-2}[/tex].
Suffix "yne" in the name of a compound represents that there is a triple bond present in the compound.
So, a molecule of propyne will have three carbon atoms, four hydrogen atoms and a triple bond. Therefore, there wll be 6 sigma bonds and 2 pi bonds in a propyne molecule.
