See image — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

# Step-by-Step Solution **Identify the carbon environments:** - $H_\alpha$: attached to a quaternary carbon (4 bonds to C) - $H_\beta$: attached to a carbon bonded to an aromatic ring - $H_\gamma$: attached to a saturated secondary carbon ($sp^3$) - $H_\varepsilon$: attached to a saturated primary carbon ($sp^3$, on $CH_3$) **Bond energy principle:** Bond energy increases with electronegativity of the atom attached to carbon. An electron-withdrawing group increases $C$-$H$ bond energy by polarizing the bond. **Rank by electron-withdrawing strength:** 1. **Quaternary C** (most $sp^3$ hybridized, least electronegative environment) → weakest $C$-$H$ bond 2. **Primary $CH_3$** (saturated, least substituted) → weak $C$-$H$ bond 3. **Secondary $CH$** (saturated, more substituted) → stronger $C$-$H$ bond 4. **Aromatic-bonded C** (sp² hybridized benzene ring, most electronegative due to resonance) → strongest $C$-$H$ bond **Order of B.E.:** $$C-H_\alpha < C-H_\varepsilon < C-H_\gamma < C-H_\beta$$ **Answer: (A)** is correct because it correctly places the weakest bond ($H_\alpha$ on quaternary C) first and the strongest bond ($H_\beta$ on aromatic C) last.