MAGOOSH OFFICIAL SOLUTION:
Split #1: pronoun problems. The CEO is clearly talking about what he wants for Brantford Industrial. Brantford Industrial is presumably a big company with lots of employees, but as a collective noun, it is singular, and must take the singular pronoun "it." The plural pronoun "they" is incorrect, and choices (A) & (B) make this mistake.
Split #2: Parallelism, part one. Clearly we have parallelism in this question, in the things that the CEO wanted to encourage. The final element is "the acquisition", so we expect other elements to have a parallel structure. The first element should be "expansion", not "expanding." Choices (A) & (E) make this mistake.
Split #3: Parallelism, part two. The big question is: how many elements are in parallel. It could be three "the expansion, … the use, … and the acquisition" or, the middle one could be the participial phrase "using," modifying the first element. Choices (C) & (D) are both 100% grammatically correct, and we have to decide purely on the basis of logic.
version (C): its expansion into promising overseas markets, the use of domestic suppliers for all materials other than oil products, and
version (D): its expansion into promising overseas markets, using domestic suppliers for all materials other than oil products, and
Version (C) implies that the CEO encouraged three different things, and that the use of domestic suppliers is a different agenda item from the overseas expansion. Version (D) implies that the CEO encouraged two different things, and that he wants the first, overseas expansion, done by using only domestic suppliers. There is something fishy about this second version: why would we want to do all business overseas with only domestic suppliers? More importantly, these are two different meanings, and version (C) is faithful to the meaning given in the prompt. Therefore, version (C) is the best answer.