Correct option is A
Option (a) contains an error.
· Explanation: The phrase "much prettier face" is incorrect because "much" should modify a comparative degree. The correct expression is "a much prettier face," where "a" properly introduces the noun "face," and "much" intensifies the comparative adjective "prettier."
· Grammatical Rule Used: When modifying comparative adjectives, we often use "much" for emphasis (e.g., "a much better option"). An article like "a" is necessary before singular countable nouns like "face."
· Example: She has a much brighter smile than her friend.