Final answer:
Transcription produces mRNA, rRNA, and tRNA molecules.
Step-by-step explanation:
Transcription is the process in which genetic information from DNA is transcribed into RNA molecules. The main types of RNA produced by transcription include messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA). mRNA carries the genetic instructions from DNA to the ribosome for protein synthesis, rRNA is a structural and catalytic component of ribosomes, and tRNA brings amino acids to the ribosome during translation.
Therefore, the correct answer is D. All of the above. Ribozymes, ribosomal proteins, and the intron (an RNA sequence removed during processing) are not directly produced by transcription.