Reaction catalysed by enzyme 'Maltose'.

The correct option is A Maltose $\to$ Glucose
Reaction catalysed by enzyme 'Maltase' is the conversion of $Maltose\to Glucose$.
$Maltose$ is a disaccharide and on hydrolysis, it gives $glucose$.
$Maltose\left(C_{12}{H}_{22}{O}_{11}\right)\underset{hydrolysis}{\overset{{}^{\prime }Maltas{e}^{\prime }}{\to }}Glucose\left(C_6{H}_{12}{O}_6\right)+Glucose\left(C_6{H}_{12}{O}_6\right)$.