Among the representatives of a symposium on public opinion representatives for traffic regulation, one was from Heilongjiang, two were northerners, one was Cantonese, two were only responsible for passenger transportation, and three were only engaged in cargo transportation. If the above introduction involved all the representatives of the symposium, who will participate in the symposium? ['The minimum may be 3 and the maximum may be 8.', 'The minimum may be 5 people, and the maximum may be 8 people.', 'The minimum may be 5 people, and the maximum may be 9 people.', 'The minimum may be 3 people, and the maximum may be 9 people.']