A restaurant owner creates an advertisement promising $25 to take part in a food taste testing trial. The owner selects the first seven people who reply to the advertisement. Which of the following is true? (3 points) a
It is not a valid sample because it does not tell the type of food.

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

c
It is a valid sample because the first seven people were selected to participate.

d
It is a valid sample because money was offered to participants.