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: Dental
Name the parts of the implant assembly 
Select and explain. 
A. 1 - fixture, 2 –  abutment, 3 - abutment screw, 4 - crown, B. 1 - crown, 2 – abutment screw, 3 - abutment. 4 - fixture, C. 1 - crown, 2 - healing cap, 3 - abutment. 4 - root form  implant, D. 1 - crown, 2 - healing cap, 3 - cover screw, 4 - fixture
B: 1 - crown, 2 – abutment screw, 3 - abutment. 4 - fixture
Answer: B: 1 - crown, 2 – abutment screw, 3 - abutment. 4 - fixture 
Explanation: None