I’m taking a guess but I would say, weak: off topic
I’m guessing this is a simple sentence sorry if I’m wrong good luck.
By reading the text you'll be able to come up with a answer.
Explanation: The rule for indefinite article usage is as follows: Use before nouns (or adjectives) that start with a consonant sound. Use before nouns (or adjectives) that start with a vowel sound.
The answer is either B or D
