There is often enough information on the card to tell you _______the book will be useful or notAwhetherBwhat Cthat选什么答案为什么选它再翻译正确的答案

A. whether

I chose option A because "whether" is used to introduce a direct question or a clause indicating a choice between two alternatives, which fits the context of the sentence. The sentence is talking about whether the book will be useful or not based on the information on the card.

正确的答案翻译：通常卡片上的信息足以告诉你这本书是否有用。