The City Council in a Suburb of Raleigh Is Interested

The city council in a suburb of Raleigh is interested in the level of public support for a tax increase to support restoration of nearby parks and waterways. A marketing research firm is hired that then selects a simple random sample of 50 adult residents and contacts each to determine whether the resident would be opposed to the tax increase. Of these respondents, 15 indicate that they would be opposed to the tax increase.
What is the sample in this example?

A) The 35 residents in favor of the increase
B) The 15 residents not in favor of the increase
C) The 50 residents selected
D) All residents in the suburb