Cracking dodecane conserves atoms Steps:

• Dodecane formula is C₁₂H₂₆; products X + Y + Z must total 12 C and 26 H.
• Analyze A: Y = but-1-ene (C₄H₈), Z = ethene (C₂H₄) gives C₆H₁₄ for X (hexane), balances equation.
• Analyze B: Octane (C₈H₁₈) leaves C₄H₈ for Y + Z; no two small alkenes total C₄H₈ with cis-trans in one.
• Analyze C: Statement assumes Y, Z are alkenes with different Mᵣ, but question lacks specifics on products. Not enough information on D to evaluate.

Why D is correct:

• Not enough information.

Why the others are wrong:

• A: Balances, so correct; but if question implies all alkenes, X as alkane invalidates.
• B: No viable Y, Z pair allows cis-trans isomerism while balancing.
• C: Assumes unspecified properties of Y, Z.

Final answer: D