Answer:
B. Service
Explanation:
It's the only one that fits the context.
Travel and tourism is a part of the service sector of the economy and employs a large number of people. As Europe has an extensive network of rail and roads. The system is an example of the modern transportation industry.
Hence the option B services is correct.
Learn more about the Europe is facilitated by an extensive railroad system.
brainly.com/question/16449112.