Sucrose yields two monosaccharides on hydrolysis, glucose and fructose. So Sucrose is a disaccharide. So option (ii) is correct.

Monosaccharide contains only one sugar ring. Sucrose contains two monosaccharide glucose and fructose. Therefore, option (i) is wrong.

A reducing sugar has free ketone or aldehyde groups and therefore contain a hemiacetal instead of an acetal. Sucrose doesn’t have a hemiacetal group. So it behaves as a non-reducing sugar. Therefore option (iv) is correct.

Reducing sugar contains hemiacetal instead of acetal group. So option (iii) is wrong.

(Sucrose)

Two monosaccharides α-D-glucose and ß-D-fructose are joined with each other to form disaccharide sucrose.