Answer:
B. national service provider (NSP), regional service provider (RSP), and internet service provider (ISP)
Step-by-step explanation:
A National service provider can simply be said to be a firm that deals in the sales of Fiber optic cables. digital subscriber lines, etc.
A Internet service provider: An internet service provider can be defined as the a firm that deals with accessing and using the internet. It can be individual or community-owned etc. Services of ISPs incliude internet transit, web hosting, etc.
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