Respuesta :
B.)It is not a valid sample because it is not a random sample of the population.
The true sentence about the sample is B. It is not a valid sample because it is not a random sample of the population.
According to the question,
The concept of random sample involves that the sample have to be representative and with the minimum bias. If the researcher wants to arrive to a conclusion about the population, eight individuals are not enough and he needs a method to select from his subsample (all individuals who respond the advertisement in a given period of time), individuals that will finally participate .
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