To solve this problem, we need to identify the enzyme responsible for transporting lactose into bacterial cells.$\newline$Let's analyze each option:$\newline \bullet$Option 1: Permease$\newline$ - Permease is a type of protein that facilitates the transport of lactose across the cell membrane.$\newline$ - It is specifically involved in the uptake of lactose into the bacterial cell.$\newline$ - Therefore, permease is the correct enzyme responsible for lactose transport.$\newline \bullet$Option 2: Polymerase$\newline$ - Polymerase is an enzyme that synthesizes long chains or polymers of nucleic acids.$\newline$ - It is not involved in the transport of lactose.$\newline \bullet$Option 3: Beta-galactosidase$\newline$ - Beta-galactosidase is an enzyme that breaks down lactose into glucose and galactose.$\newline$ - It functions after lactose has been transported into the cell, not during transport.$\newline \bullet$Option 4: Acetylase$\newline$ - Acetylase is an enzyme that adds acetyl groups to molecules.$\newline$ - It is not involved in lactose transport.$\newline$Based on the analysis, the correct option is Option 1: Permease, as it is responsible for transporting lactose into the bacterial cell.