The number of chiral carbon atoms in glucose and fructose are

Which of the statements about 'denaturation' given below are correct?

Statements:

($\mathrm{i}$) Denaturation of proteins causes loss of secondary and tertiary structures of the protein.

($\mathrm{ii}$) Denaturation leads to the conversion of double strand of $\mathrm{DNA}$ into single strand.

($\mathrm{iii}$) Denaturation affects the primary structure, which gets destroyed.