Vitamins are similar because they are made of the same elements－usually carbon, hydrogen, oxygen, and sometimes nitrogen. They are different ________their elements are arranged differently.
句意：维生素是相似的，因为它们由相同的元素组成——通常是碳、氢、 氧，有时是氮。它们的不同之处在于它们的元素排列方式不同。in that因为；由于。so that以便；所以。such that如此……以致。except that只可惜；除了……之外。根据句子意思，前后应当表示因果，所以用in that。故正确答案为A。