Task: Question Answering
Input (English): Passage: Over the past year , we 've had a number of family get-togethers at my house . More often than not , my dad was the one who did the cooking on his barbecue grill . Everyone seemed to really love his cooking , especially when it came off of that grill . He would usually prepare for one of these little barbecue parties a day in advance by making sure that he had charcoal and lighter fluid to get the grill started . Depending on what was being made , my dad would figure out just how much charcoal he would need to use , and would lay it out inside the grill . He 'd then use paper from the bag of charcoal , light the paper up , and spray it with lighter fluid to ensure that the charcoal caught fire . Whether it was burgers , hot dogs , ribs , chicken , or steak , my dad always knew how to grill it . Question: When did the dad know the coals were hot enough? Option1: when the coals fully changed color. Option2: when the coals were still on fire.
Output (English): when the coals fully changed color.