Answer:
because she is the one story is talking about, therefore, she is the <em><u>subject matter</u></em>
Here's link to the answer:
tinyurl.com/wpazsebu
Answer by Mimiwhatsup: B. Mustafa is an excellent long-distance runner, and he won the race last weekend.
Source: "One of the two “voices” of verbs (see also passive voice). When the verb of a sentence is in the active voice, the subject is doing the acting, as in the sentence “Kevin hit the ball.” Kevin (the subject of the sentence) acts in relation to the ball." (https://www.dictionary.com/browse/active-voice)
Why: Mustafa is the subject of the sentence and it works with him winning the race.