This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Environment and health, Subject name: Social & Preventive Medicine
What is the approximate penetrating ability of alpha paicle radiation at tissue level - 
Select and explain. 
A. 0.05 mm, B. 0.10 mm, C. 1.50mm, D. 2.00 mm
A: 0.05 mm
Answer: A: 0.05 mm 
Explanation: Park's textbook of preventive and social medicine 23rd edition. * Alpha paicles approximate penetrating ability - 4cm - 0.05 cm - 0