Aresearcher posts a newspaper advertisement offering $10 in exchange for participation in a short study. the researcher accepts the first 10 people who respond to the advertisement. which of the following statements is true about the sample? a. it is a valid sample because money is offered to participants. b. it is not a valid sample because it is only a short study. c. it is a valid sample because the first 10 people were selected to participate. d. it is not a valid sample because it is not a random sample of the population.

D. It is not a valid sample because it is not a random sample of the population.

Step-by-step explanation:

When a researcher wants to know about the some thing, he/she has to take a sample from the population.

Example, consider a researcher wants to know how many hours the students study at home in a week, so the researcher has to take the sample from the student's population.

Here, he/she gives the advertisement and offers $10 for 10 people. Therefore, anyone can come they may not required for a particular study.

Therefore, answer is D)  It is not a valid sample because it is not a random sample of the population.