The correct statements are :
A. Activation energy for enzyme catalysed hydrolysis of sucrose is lower than that of acid catalysed hydrolysis.
B. During denaturation, secondary and tertiary structures of a protein are destroyed but primary structure remains intact.
C. Nucleotides are joined together by glycosidic linkage between $$C_{1}$$ and $$C_{4}$$ carbons of the pentose sugar.
D. Quaternary structure of proteins represents overall folding of the polypeptide chain.
Choose the correct answer from the options given below :

Analyzing statements about biomolecules.

A. Enzyme-catalyzed reactions have lower activation energy than acid-catalyzed. Correct.

B. During denaturation, secondary and tertiary structures are destroyed but primary structure (peptide bonds) remains intact. Correct.

C. Nucleotides are joined by phosphodiester linkage, not glycosidic linkage. Incorrect.

D. Quaternary structure represents the arrangement of multiple polypeptide chains, not overall folding (that's tertiary). Incorrect.

Correct: A and B only.

The answer is Option 2: A and B only.