Answer:
b. After two hours have passed, stop eating foods left out at room temperature.
Step-by-step explanation:
According to USDA (United States Department of Agriculture), cooked food that is left at room temperature has a higher risk of being unsafed than the one that is refrigerated. This is because, at room temperature (40F- 140 F approximately) bacteria grows in the food and therefore it is unsafe to eat.
According to this Department, the bacteria double its number every 20 minutes approximately so the Department considers that, after two hours standing at room temperature, food is no longer safe to eat anymore.