Which statement correctly distinguishes DNA and RNA in protein synthesis?

• A. DNA directly catalyzes protein synthesis
• B. RNA stores genetic information and DNA helps in transcription
• C. Proteins are encoded directly by RNA without DNA
• D. DNA stores genetic information and RNA helps in transcription and translation

Answer: (D)

The main idea is how genetic information is used to make proteins. DNA stores the instructions for building proteins, and RNA carries and uses that information to synthesize them. This flow of information—DNA to RNA to protein—is the backbone of how cells convert genetic code into functional molecules. The statement that accurately captures this is that DNA stores genetic information and RNA participates in both transcription (copying DNA into RNA) and translation (using that RNA to assemble amino acids into a protein).

DNA isn’t the catalyst for protein synthesis—ribosomes and other enzymes carry out the actual building. The notion that RNA stores genetic information isn’t correct for most cellular organisms, where DNA is the information store and RNA serves as the messenger and adaptor during protein assembly. It’s also not accurate to say proteins are encoded directly by RNA without any transcription, since the standard pathway involves transcription of DNA into RNA before translation into protein.