Answer: I think it's D
Step-by-step explanation: I say the answer is (B) because in the full question, it's asking how much would 2.5 means, therefore, you're multiplying, to get 125.
If 1cm=50km Then 2.5 is 50km, 50km, 25
50+50+25=125, or simply just multiply. 25 is half of 50, so with the 2.5 there, doesn't make it a whole number, therefore, making the 25 in it's place, because of the 2.5.