The HBr Synthesis Is Thought to Involve the Following Reactions $\rightarrow$

The HBr synthesis is thought to involve the following reactions:
1.Br₂ $\rightarrow$ 2Br.
2.Br. + H₂ $\rightarrow$ HBr + H.
3.H. + Br₂ $\rightarrow$ HBr + Br.
4.2Br. $\rightarrow$ Br₂
5.2H. $\rightarrow$ H₂
6.H. + Br. $\rightarrow$ HBr
The chain propagation reactions in this mechanism are reactions"

A) 6.
B) 1, 2, 3, and 6.
C) 2 and 3.
D) 1, 2, and 3.
E) 2, 3, and 6.