Passage Potassium Permanganate (KMnO₄) Is a Highly Reactive Inorganic Salt That

Passage
Potassium permanganate (KMnO₄) is a highly reactive inorganic salt that appears as granular dark purple crystals, nearly black in color.  Due to its useful chemical properties and the fact that its reactions typically do not produce compounds that are toxic, KMnO₄ is employed in a variety of applications, including use as a topical skin disinfectant, an antifungal agent, a fire starter, and a disinfectant for drinking water.KMnO₄ is widely used as an alternative water treatment agent both to disinfect drinking water and to remove undesirable dissolved iron and sulfur compounds.  The crystals are highly soluble in water and form bright pink aqueous solutions that provide a visual indication of the presence of KMnO₄ treatment residual.  As a drinking water disinfectant, a KMnO₄ concentration of 1 mg/L is recommended unless higher levels of contamination are indicated by the absence of a pink residual.Industrial production of potassium permanganate is accomplished in two steps.  In step 1, manganese(IV) oxide (MnO₂) is heated with potassium hydroxide in the presence of oxygen to produce potassium manganate (K₂MnO₄) , as outlined in Reaction 1.2 MnO₂ + 4 KOH + O₂ → 2 K₂MnO₄ + 2 H₂OReaction 1In step 2, the potassium manganate is then converted into potassium permanganate electrochemically according to Reaction 2.2 K₂MnO₄ + 2 H₂O → 2 KMnO₄ + 2 KOH + H₂Reaction 2
-In which compound does manganese have a +6 oxidation number?

A) MnO
B) MnO₂
C) K₂MnO₄
D) KMnO₄