Correct Answer - B::C
The maximum O.S. of Tl is `+3`, therefore, Tl in `TlCl_(3)` cannot increases its O.S. beyond +3. Further, since +1 O.S. of Tl is much more stable than +3, therefore, Tl in `TlCl` is not likely to increase its O.S. to +3 . Thus, both `TlCl_(3)` and `TlCl` do not undergo disproportionation. Thus. options (b) and (c ) not correct.
