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: Social & Preventive Medicine
Overall most common cancer in wold 
Select and explain. 
A. Lung cancer, B. Colon cancer, C. Breast cancer, D. Thyroid carcinoma
A: Lung cancer
Answer: A: Lung cancer 
Explanation: None