To solve this problem, we need to understand the dehydration reaction that links two glucose molecules to form maltose.$\newline$Let's analyze the process step-by-step:$\newline \bullet$Glucose has the molecular formula $C_6H_{12}O_6.\newline \bullet$When two glucose molecules combine, they undergo a dehydration reaction.$\newline \bullet$In a dehydration reaction, a water molecule $(H_2O)$ is removed.$\newline \bullet$The reaction can be represented as:$\newline$ $C_6H_{12}O_6 + C_6H_{12}O_6 \rightarrow C_{12}H_{22}O_{11} + H_2O\newline \bullet$Here, two glucose molecules combine to form one maltose molecule $(C_{12}H_{22}O_{11})$ and one water molecule $(H_2O).\newline$Therefore, the molecular formula for maltose is $C_{12}H_{22}O_{11}.\newline$This corresponds to Option 3.