The above excerpt is part of a dialogue in which a mother gave her son a garlic-flavored cookie because he asked for a cookie. After tasting it he says it tastes bad and the mother says "やっぱりまずい？" I thought やっぱり meant "I knew it" so I thought the mother was trying to say "I knew it would taste bad." What is confusing me is why is "やっぱりまずい？" a question. It sounds like she is saying instead "I knew it would taste bad?" which doesn't make sense.