When Greenway Ins. sells 48,000 units, its total fixed cost is 115,200. What is the total fixed cost when is sells 54,000 units?

A. 100,800 B.115,200 C.129,600 D. It cannot be determined

Is the answer 115,200 because fixed cost always stay the same?

OR 115,200/48,000=2.4...... THEN 2.4*54,000=129,600??

I've seen this question on Chegg, but both answers are said to be correct according to other people.