Potassium permanganate (KMnO\(_4\)), a potent oxidizing agent, reacts with HCl. In this reaction, KMnO\(_4\) oxidizes chloride ions (Cl\(^-\)) from HCl to chlorine gas (Cl\(_2\)), as shown in the equation:\[\text{2 Cl}^- + \text{2 H}^+ → \text{Cl}_2(g) + \text{H}_2\text{O}\]Because chlorine gas (Cl\(_2\)) is also a strong oxidizing agent, it competes with the oxidation process involving KMnO\(_4\). This interference prevents HCl from effectively functioning as an acidic medium for KMnO\(_4\) oxidation reactions, rendering HCl unsuitable for this purpose.
Final Answer: \[\boxed{\text{The correct answer is (2), KMnO}_4\text{ oxidizes HCl into Cl}_2\text{, which is also an oxidizing agent.}}\]