Correct Answer: B. RCO+
Detail about MCQs
The acylium ion is a cationic species with a positive charge on the carbon atom of the carbonyl group (CO). It is a reactive intermediate often involved in acylation reactions, where it acts as an electrophile by accepting a pair of electrons during a chemical reaction. This is commonly seen in organic chemistry reactions involving acyl halides, anhydrides, or other acylating agents.