Glucose and fructose are

Compound $A$,$C_5H_{10}O_5$,gives a tetraacetate with $Ac_2O$ and oxidation of $A$ with $Br_2-H_2O$ gives an acid,$C_5H_{10}O_6$. Reduction of $A$ with $HI$ gives isopentane. The possible structure of $A$ is:

Identify the monomer of starch.

Sugar $X$:
$A.$ is found in honey.
$B.$ is a keto sugar.
$C.$ exists in $\alpha$ and $\beta$-anomeric forms.
$D.$ is laevorotatory.
$X$ is

$C_{1}-C_{4}$ glycosidic bond is not found in

Which carbon atoms of fructose are bonded together through oxygen forming fructofuranose?