Define homologous series.

Identify the general formula for alkyl groups $\mathrm{cm}$.

$$\begin{gathered} \mathrm{A}: {\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}+2} \\ \mathrm{B}: {\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}} \\ \mathrm{C}: {\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}+1} \end{gathered}$$

(Enter your correct answer as $\mathrm{A}, \mathrm{B} \mathrm{or} \mathrm{C}$)

Name the alkyl group of: