The Harry Potter series, written by J.K. Rowling, is perhaps the most popular set of novels of the modern era. With seven books and many successful films to its name, the series has gathered about 15 billion dollars in sales. How did the series become so popular? The reason can be broken down into several areas.The first book in the series was rejected 12 times before it was picked up by Bloomsbury—a small publisher in England. So receiving this contract was Rowling's first step to success. However, getting a book contract does not ensure the success of a book. The story was soon loved by children and adults alike. In light of this, Bloomsbury Publishing published a second version of the books with “adult” (less colorful and more boring) book covers. This made it easier for a full range of ages to enjoy the series.Another factor that worked like a charm was that the publisher and Rowling herself, through the books, conducted midnight releases, promotions, and pre-ordering more readers. Customers who feared that their local bookstore would run out of copies responded by pre-ordering over 700,000 copies before the July 8, 2000 release.What does the underlined word “releases” (Para. 3) mean?A. The activity that frees or expresses energy or emotion.B. The announcement about the book’s publishing information.C. The sales of books that is available only at midnight.

我们来一步一步分析这个题目。

题目问的是：第三段中划线单词 “releases” 的意思是什么？我们需要根据上下文来推断这个词的含义。

先看原文第三段内容：

> Another factor that worked like a charm was that the publisher and Rowling herself, through the books, conducted midnight releases, promotions, and pre-ordering more readers. Customers who feared that their local bookstore would run out of copies responded by pre-ordering over 700,000 copies before the July 8, 2000 release.

我们逐句理解：

• “Another factor that worked like a charm” 意思是“另一个非常有效的因素”。
• “the publisher and Rowling herself... conducted midnight releases, promotions, and pre-ordering...” 出版商和罗琳本人组织了“午夜发布”、促销活动和预售活动。
• 接着说，顾客担心书店会售罄，于是提前预定了超过70万册。

关键词是 “midnight releases” —— “午夜发布”。这里的“发布”显然指的是新书在午夜正式上市、发售的活动。这在《哈利·波特》系列中是著名的现象：粉丝们会在书店通宵排队，等到午夜时分第一时间买到新书。

因此，“releases” 在这里指的是“新书的发布、发售”，即书籍正式向公众出售的行为。

现在我们来看选项：

A. The activity that frees or expresses energy or emotion.
（释放或表达能量或情绪的活动）
→ 这是“release”作为“释放情感”的意思，比如“a release of anger”，不符合语境。

B. The announcement about the book’s publishing information.
（关于书籍出版信息的公告）
→ 这个接近，但“announcement”是“宣布”，而文中“midnight releases”指的是实际的发售活动，不仅仅是宣布信息。比如，7月8日是“release”时间，人们预购是为了在那天拿到书，而不是仅仅听到消息。所以这个选项不够准确。

C. The sales of books that is available only at midnight.
（仅在午夜进行的书籍销售）
→ 这个选项虽然说“only at midnight”（只在午夜），略显绝对，但整体上描述的是“午夜发售书籍”的活动，与文中的“midnight releases”完全对应。虽然实际上销售可能持续多日，但“午夜发售”是首发时刻，这个选项最贴近文意。

综合判断：

“releases” 在这里指的是“新书的发布/发售活动”，尤其是“午夜发售”这一特殊形式。

因此，最合适的答案是：

C. The sales of books that is available only at midnight.

虽然“only at midnight”有点绝对，但在上下文中，这是强调午夜首发的销售活动，符合《哈利·波特》新书发布时的真实情况。

✅ 正确答案：\boxed{C}