参考答案

正确答案：A
解析：词义题型根据上下文(尤见本段中But if you open your mind as widely as possible，then signs and hints of almost imperceptible ineness，from the twist and turn of the first sentences，will bring you into the presence of a human being unlike any other．)可以推断出imperceptible与本句中的impalpable同义，因此A为答案。