The ratio of the relative intensities of the carbon signals in the first order ${ }^{13} \mathrm{C} \mathrm{NMR}$ spectrum of $\mathrm{CD}_{3} \mathrm{Cl}$ is
(a)1:4:6:4:1
(b)1:3:3:1
(c)$1: 6: 15: 20: 15: 6: 1$
(d)$1: 3: 6: 7: 6: 3: 1$
Answer
Answer: D ✓ checked by 4AB · confidence high
Explanation
Coupling to three deuterons (I = 1) gives 2nI + 1 = 7 lines with intensities 1:3:6:7:6:3:1.