Give the structure and `IUPAC` name of disaccharide, which gives the reactio given below:

Given, `(A)` does not reduce Fehling's solution and does not mutarotate.

Explanation

(i). It does not reduce Fehling's solution and does not mutarotate, which suggests that hemiacetalic `OH` group at `C-1` of glucose and hemiketalic `OH` group at `C-2` of fructose are not free and are involved in glycosidic linkage.
ii. Hydeoysis by maltose suggests `alpha-`linkage and hydrolysis by emulsin suggests `beta-`linkage.
ii. Hydrolysis by maltase suggests `alpha-`linkage and hydrolysis by emulsin suggests `beta-`linkage.
iii. Products obtained after the methylation and hydrolysis of `(A)` suggest `(C-1) (OH) (alpha)` of glucose and `(C-2) (OH) (beta)` of fructose are involved in glycosidic linkage.
iv. Glucose is in puranose form which suggests a six-membered ring.
v. Fructose is in furanose form and this suggests a five-membered ring.
All the observations suggest that `(A)` is sucrose.