This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Translation, Subject name: Biochemistry
Which of the following toxin inhibits the peptidyl transferase? 
Select and explain. 
A. Ricin, B. Diphtheria toxin, C. Peussis toxin, D. Amanitin
A: Ricin
Answer: A: Ricin 
Explanation: Ricin In the seeds of castor beans (Ricinus communis) Glycosidase-cleaves an adenine residue from the 28S rRNA (peptidyl transferase) Lethal dose - 500 mg