Answer: (C) the 2633 viewers who phoned in.
Explanation:
In statistics , a sample is a countable subset of a large population that represents the entire population.
Given : A television station is interested in predicting whether or not voters are in favor of an increase in the state sales tax.
It asks its viewers to phone in and indicate whether they support or are opposed to an increase in the state sales tax in order to generate additional revenue for education.
Of the 2633 viewers who phone in, 1474 (55.98%) are opposed to the increase.
i.e. 1474 out of 2633 viewers opposed to the increase.
Clearly , 2633 viewers are representing the entire population of viewers.
Hence, the sample obtained is the 2633 viewers who phoned in.