A hydrocarbon compound is calculated to have an Index of Hydrogen Deficiency (IHD) or Degree of Unsa — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

The DU value represents the sum of the number of rings and the number of $\pi$ bonds in the molecule. A DU of 2 means the sum must equal 2. This can be achieved structurally via: two separate double bonds ($1+1=2$), one triple bond (contains two $\pi$ bonds = 2), one ring and one double bond ($1+1=2$), or two rings ($1+1=2$). Therefore, all given options are physically possible structural features.