Concept:Aromatic hydrocarbons such as benzene have a sweet smell and undergo substitution reactions instead of addition reactions.
Explanation:A hydrocarbon contains only carbon and hydrogen.
Among the options, benzene and methane are hydrocarbons, while alkanol and ester contain oxygen.
Benzene, with formula
C6H6, is a colourless liquid with a sweet smell.
It undergoes electrophilic substitution reactions such as nitration and halogenation.
Methane also undergoes substitution, but it does not have a sweet smell.
Therefore, the hydrocarbon described is benzene.
Answer:B. benzene