This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
Which of the following anticancer drugs are competitive inhibitors of tyrosine kinase? 
Select and explain. 
A. Imatinib and Sunitnib, B. Letrozole, C. Bicalutamide, D. Fulvestrant
A: Imatinib and Sunitnib
Answer: A: Imatinib and Sunitnib 
Explanation: None