Twiigs is an online polling website that allows users to easily create polls and to vote on polls created by other users. A March2010 poll asked, "Has concern about autism influenced your decision about whether to vaccinate your child?" Of the 182 votescast, 80% selected "No, I'm not worried about it."Which type of sample was used in this poll?simple random samplestratified random samplemultistage random samplevoluntary response sample