Answer:
C. Ethernet over multi mode fiber .
Step-by-step explanation:
Given that the distance to be covered is 1 km. Multi-mode optic fiber is best suited for short distances of up to 2 km and can withstand harsh environments with less signal attenuation. Single mode fiber is best suited long distance of up to 200 km or more and is expensive as compared to multi-mode fiber Ethernet over twisted pair is best for indoor use and can only cover very short distances. Although UTP and STP are relatively cheap they cannot withstand harsh environments without great signal loss.