In M, S, Word the wrong word is underlined with………….. colour.

In MS Word, the application uses different underline colours to indicate possible mistakes while typing:
Red underline → Indicates a spelling mistake.
Example: If you type "recieve" instead of "receive", Word will underline it in red.
Green underline → Indicates a grammatical mistake.
Example: Wrong sentence structure like "He go to school" will be underlined in green.
Blue underline → Indicates a contextual or formatting suggestion (introduced in later versions).
Example: Using "their" instead of "there" may be underlined in blue.
Therefore, when a wrong word (spelling error) is typed in MS Word, it is underlined with red colour.