$(1)$ Denaturation of proteins causes loss of secondary and tertiary structures of the protein.

$(2)$ Denaturation leads to the conversion of double strand of $DNA$ into single strand.

$(3)$ Denaturation affects primary structure which gets distorted.

$(A)$ Nucleotide form from nucleoside and phosphate group by ether linkage

$(B)$ In nucleoside, nitrogenous base link with hexose sugar of $DNA$ or $RNA$

$(C)$ $DNA$ and $RNA$ are differ in only nature of sugar

$(D)$ $A = T$ and $C \equiv G$ are hydrogen bond between nitrogenous base