Which is the chemical test for polysaccharide?

The pentose sugar in $DNA$ and $RNA$ has a ......... structure.

Which of the following is a reducing sugar?

In addition to the aldehyde group,glucose contains . . . . . . .

Match List-$I$ with List-$II$:

List-$I$	List-$II$
$(a)$. Sucrose	$(i)$. $\beta-D$-Galactose and $\beta-D$-Glucose
$(b)$. Lactose	$(ii)$. $\alpha-D$-Glucose and $\beta-D$-Fructose
$(c)$. Maltose	$(iii)$. $\alpha-D$-Glucose and $\alpha-D$-Glucose

Choose the correct answer from the options given below:

Sugar is the main source of energy as it produces energy on metabolic decomposition. But these days low calorie drinks are more popular,why?