Discussion

The correct match between Column I and Column II is :

Column I	Column II
(i) p-xylene	(a) one signal in ¹H-NMR and two signals in ¹³C-NMR
(ii) 4-methyl cyclohexanone	(b) 2210 cm⁻¹ in IR
(iii) 1-Butyne	(c) Two singlets in ¹H-NMR
(iv) 2, 2-dimethyl propane	(d) λ_max 280 (∈ 30) in UV

Answer: B

The correct match is (i-c) (ii-d) (iii-b) (iv-a).

p-Xylene shows two singlets in ¹H-NMR, the four ring H and the six methyl H (c).
4-Methylcyclohexanone, a saturated ketone, has the weak n→π* band near 280 nm with ε about 30 (d).
1-Butyne has a C≡C stretch in the IR, which the key places at 2210 cm⁻¹ (b).
2,2-Dimethylpropane has twelve equivalent H, one ¹H signal, and two kinds of carbon, two ¹³C signals (a).

Option A gives p-xylene a single proton signal, which ignores the aromatic H, and options C and D give the UV band of a ketone to an alkyne.

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