The bond between carbon atom (1) and carbon atom $(2)$ in compound $\mathrm{N} \equiv \mathrm{C}-\mathrm{CH}=\mathrm{CH}_{2}$ involves the hybridization
(a) $\mathrm{sp}^{2}$ and $\mathrm{sp}^{2}$
(b) $\mathrm{sp}^{3}$ and sp
(c) sp and sp²
(d) sp and sp