Nucleic Acids Questions in English

(A) In $DNA$, the consecutive deoxynucleotides are linked through a phosphodiester linkage. This linkage is formed between the $3'$-hydroxyl group of one sugar and the $5'$-phosphate group of the next sugar.

(A) The double helical structure of $DNA$ is primarily stabilized by $hydrogen$ bonds between the complementary nitrogenous bases ($Adenine$ with $Thymine$ and $Guanine$ with $Cytosine$).
These $hydrogen$ bonds hold the two strands of the $DNA$ double helix together.

(C) $DNA$ and $RNA$ are chiral molecules due to the presence of chiral $2$-deoxy-$D$-ribose and $D$-ribose sugar units, respectively.

(D) $RNA$ contains the nitrogenous bases adenine, guanine, cytosine, and uracil.
Thymine is a base found in $DNA$, but it is replaced by uracil in $RNA$.
Therefore, thymine-containing nucleotides are not naturally present in $RNA$.

(A) $DNA$ generally exists as a double-stranded helix and contains Adenine $(A)$, Guanine $(G)$, Cytosine $(C)$, and Thymine $(T)$ as its nitrogenous bases.
$RNA$ is typically single-stranded and contains Uracil $(U)$ instead of Thymine $(T)$.

(C) The genetic information in $DNA$ is encoded in the specific order or sequence of nitrogenous bases ($Adenine$, $Thymine$, $Cytosine$, and $Guanine$) along the sugar-phosphate backbone. This sequence acts as a code that determines the synthesis of proteins and the traits of an organism.
Therefore, the correct option is $C$.