Correct Answer: A
Explanation:
The missing word describes the matter being discussed with knowledge being the other aspect of the same matter. Therefore, it becomes evident that the missing word cannot be close to ‘ignorance’ or ‘unawareness’ in meaning as they are both antonyms of ‘knowledge’. Out of the remaining answer options, ‘belief’ and ‘conviction’ are the only two words that mean the same and either of them can be placed in the blank to impart a logical meaning to the sentence. Therefore, A and C are the correct answers.