$\begin{array}{1 1} \text{(a) Haloform reaction starts with the disproportionation of the halogen with the presence of the HCl} \\ \text{(b)Haloform reaction starts with the disproportionation of the halogen with the presence of the hydroxide ion} \\ \text{(c) Haloform reaction starts with the disproportionation of the hydrogen with the presence of the hydroxide ion} \\ \text{(d) Haloform reaction starts with the disproportionation of the halogen with the presence of the $H_2SO_4$}\end{array} $