At US Data Corporation's Web Site, They Advertised That "Because

At US Data Corporation's web site, they advertised that "Because of our commitment to quality
And our vast amount of industry knowledge and experience, we have grown to be one of
America's leading providers of mailing lists, marketing data, sales leads and research data.We
Maintain databases of information on consumers and businesses nationwide that set industry
Standards for mission critical currency, reliability and accuracy." Trying to reach 500 potential
Donors for their annual phone donation campaign, a local fire department purchased a list of
Donors from the company.This list is an example of a

A) stratified sample
B) systematic sample
C) judgment sample
D) frame