To determine if students at Grant High School are satisfied with the new menu items added to the school lunch program, Mr. Curtis hands out a survey to 100 randomly selected juniors in their homeroom period. It asks them to rate their level of satisfaction with this year's food service. Based on this description, the type of sampling bias most likely to affect the survey results is: Answer choices:
self-selection bias.
nonresponse bias.
undercoverage bias.