Which of the Following Steps Are a Part of Chain

Which of the following steps are a part of chain reaction during alkane substitution?
I. Propagation
II. Initiation
III. Competition
IV. Dehalogenation
V. Termination

A) I) , II) and V)
B) I) , III) and V)
C) II) , III) and V)
D) I) , II) and IV)
E) III) , IV) and V)