Two monomers in maltose are:

$\displaystyle \alpha$-D-glucose and $\displaystyle \alpha$-D-Fructose

$\displaystyle \alpha-\mathrm{D}$-glucose and $\displaystyle \alpha-\mathrm{D}-$ glucose

$\displaystyle \alpha$-D-glucose and $\displaystyle \alpha$-D-galactose

$\displaystyle \alpha-D-$ glucose and $\displaystyle \beta-D-$ glucose