This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General Pharmacology, Subject name: Pharmacology
Prodrug is 
Select and explain. 
A. Levodopa, B. Amitryptiline, C. Primidone, D. Digitoxin
A: Levodopa
Answer: A: Levodopa 
Explanation: (Levodopa) (20-KDT) (23-24-KDT 6th)PRODRUGACTIVE-FORMLevodopaDopamineEnalaprilEnalaprilata-methyldopaa methylnorepinephrineDipivefrineEpinephrineSulindacSulfide metaboliteHydrazide MAO inhibitorsHydrazine derivativesProguanilProguanil triazine PRODRUGACTIVE-FORMPrednisonePrednisoloneBecampicillinAmpicillinSulfasalazine5-Aminosalicyclic acidCyclophosphamideAldophosphamide, phosphoramide mustard, acroleinFluorouracilFluorouridine monophosphateMercaptopurineMethyl mercaptopurine ribonucleotide