(A) CrO2Cl2 (B) HNO2 (C) PH4. 19. In which of the following compounds does the underlined element have an oxidation number of +2?

(A) CrO2Cl2 (B) HNO2 (C) PH4. 19. In which of the following compounds does the underlined element have an oxidation number of +2?