(N/A) The molecular formula $C_{7}H_{8}O$ corresponds to the methyl-substituted phenols,also known as cresols. There are three isomers possible for monohydric phenols with this formula:
$1$. $2$-Methylphenol ($o$-Cresol): The methyl group is at the ortho position relative to the hydroxyl group.
Structure: $A$ benzene ring with an $-OH$ group at position $1$ and a $-CH_{3}$ group at position $2$.
$2$. $3$-Methylphenol ($m$-Cresol): The methyl group is at the meta position relative to the hydroxyl group.
Structure: $A$ benzene ring with an $-OH$ group at position $1$ and a $-CH_{3}$ group at position $3$.
$3$. $4$-Methylphenol ($p$-Cresol): The methyl group is at the para position relative to the hydroxyl group.
Structure: $A$ benzene ring with an $-OH$ group at position $1$ and a $-CH_{3}$ group at position $4$.