Refer to the Following Paragraph to Answer the Questions Below

Multiple Choice

Refer to the following paragraph to answer the questions below.
The Young Children's Charity would like to provide an accurate estimate of how much it costs to raise a child between the ages of 2 and 12 each year for its fundraising campaign. They contracted with you to find out how much households spent on raising a child in 2006 for clothing, toys/recreation, education, baby sitting, and a percentage of the expenses for family food, utilities (electricity and gas) , transportation, and rent or house payments. They gave you a list 4 million residential telephone customers in the area they will operate the campaign. You sampled every 4,000th address on the list. The Charity will have a professional survey company contact each sampled household by telephone and ask whether or not there is a child between 2 and 12 years old living in the household. If there is, their interviewers will ask other questions and record the total amount spent raising a child in the past two months. They will multiply this amount by 6 to get an annual cost.
-How large is his sample?

A) 500
B) 1,000
C) 1,500
D) 2,000
E) 20,000