Question

A researcher posts an online advertisement offering $25 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 not a valid sample because it is only a short study.
B. It is a valid sample because money was offered to participants.
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

Answer 1

@Michele_Laino

Answer 2

hint:
among those 10 people is there a valid student? Or most probably there is a poor student?

Answer 3

is it C?

Answer 4

I think D, since those 10 people have not been selected randomly

Answer 5

oh okay i see ur point ^.^

Answer 6

they were selected under a condition

Answer 7

oh okay thx

Answer 8

thanks!