Which functional group has a general formula of CnH2n+1?
All hydrocarbon compounds that have a functional group, such as CnH2n+1 , are known as alkyl compounds.
Alkyl is a functional group of an organic chemical that contains only carbon and hydrogen atoms, which are arranged in a chain. If we look at the general formula it shows one hydrogen less than the alkane series general formula.
Conclusion: The correct option is (D): Alkyl