Harry Noller's Experiments in Which He Extracted the Ribosomal Proteins

Harry Noller's experiments in which he extracted the ribosomal proteins and found that RNA molecules could catalyze protein synthesis had one major flaw. What was the flaw?

A) the extraction process may have altered the RNA molecules ​
B) protein synthesis may have occurred prior to extraction
C) coenzymes, which were not extracted, might have been responsible for the reaction
D) the extraction process may have altered the pH of the environment
E) undetectable amounts of protein may have remained