The carbonyl resonance in ${}^{13}\mathrm{C}$ NMR spectrum of $\mathrm{[(\eta^{5}\text{-}C_5H_5)]Rh(CO)]_3}$ (${}^{103}\mathrm{Rh}$, nuclear spin, I=1/2, 100 %) shows a triplet at $-65^{\circ}$ C owing to the presence of
(a)Terminal CO
(b)$\mu_{2}\text{-}\mathrm{CO}$
(c)$\mu_{2}\text{-}\mathrm{CO}$
(d)$\eta^{5}\text{-}\mathrm{C_5H_5}$
Answer
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