The probability of a randomly selected adult in one country being infected with a certain virus is 0.004. In tests for the virus, blood samples from 21 people are combined. What is the probability that the combined sample tests positive for the virus? Is it unlikely for such a combined sample to test positive? Note that the combined sample tests positive if at least one person has the virus. The probability that the combined sample will test positive is (Round to three decimal places as needed.) Is it unlikely for such a combined sample to test positive? O A. It is unlikely for such a combined sample to test positive, because the probability that the combined sample will test positive is less than or equal to 0.05, O B. It is unlikely for such a combined sample to test positive, because the probability that the combined sample will test positive is greater than 0.05. O C. It is not unlikely for such a combined sample to test positive, because the probability that the combined sample will test positive is less than or equal to 0.05, O D. It is not unlikely for such a combined sample to test positive, because the probability that the combined sample will test positive is greater than 0.05