Why Is Calling Long Distance Often More Expensive on Weekdays

Why is calling long distance often more expensive on weekdays between 8 am and 5 pm than in the evening hours?

A) Telephone companies hope to discourage customers from calling long distance during the day to keep their labour costs down.
B) The cost of making long-distance connections is higher during the day than in the evenings.
C) Businesses who must call suppliers or customers during business hours have few alternatives and therefore have an inelastic demand during the workday compared to after-work hours.
D) Increasingly, businesses who must call suppliers or customers during business hours resort to the Internet, thereby reducing demand for long-distance calls.To make up for this fall in demand, telephone companies charge higher rates.