Two statements, Assertion and Reason are given. Choose the correct option from the following. Assertion: In the secondary structure of RNA, double helix structure is formed. Reason: In the double structure of RNA, two nucleic acid chains are wound about each other and held together by hydrogen bonds between pairs of bases

Step-by-step solution

Assertion is correct: RNA is single-stranded, but its secondary structure involves the strand folding back on itself to form localised double-helical regions (e.g., stem-loops in tRNA, hairpin loops). Reason is incorrect: The double-helical regions in RNA are formed by intramolecular hydrogen bonding within a single chain, not by two separate nucleic acid chains wound around each other. That description applies to DNA, not RNA. Assertion is correct but Reason is incorrect.