নিচের কোন বানানটি সঠিক?

Explanation: The correct spelling is Option C: Questionnaire. Explanation: The correct form of the word has double 'n' and 'e' at the end, which is used to refer to a set of questions. Option A, Option B, and Option D contain spelling errors, as they miss necessary letters. Note: Correct spelling is essential for clear communication and prevents misinterpretation of meaning.