2) Which of the following is NOT voluntary response sample? d) A radio host asks listeners to go online and take a survey on his website about their opinion of his show b) A researcher randomly selects 50 students to participate in a survey by sending the survey to the 50 selected students via email. a) A professor posts a sign-up sheet outside of her classroom and lets students decide if they'd like to participate in the course. At a birthday partyteams for a game are chosen by putting everyone's name into a jar and then choosing the names at random for each team