Question 3 is based on the news report you have just heard.

听力原文：

    （3）One dog has been killed and multiple dogs have been injured by a snowmobile driver in what appears to be an intentional attack on competitors in the Iditarod Race in Alaska.

    Aliy Zirkle was the first to report an attack. A snowmobile driver had repeatedly attempted to harm her and her team, and one of Zirkle’s dogs had received a non-life-threatening injury. Zirkle reported the attack when she arrived in Nulato, Alaska, in the early hours of morning. （4） Then Jeff King, a four-time champion, reported a similar attack. His team was hit by a snowmobile driver, injuring several dogs and killing a 3-year-old male dog.

    Reporter Zachariah Hughes says that neither King nor Zirkle was injured. Although this incident very much alters the race of the two participants competing for a win, both are going to continue on their way toward the finishing line. Alaska State Troopers released a statement saying they’ve arrested Arnold Demoski, 26. He faces trial on several charges. 

3. What is the news report mainly about?

解析：C。本题目为主旨题。问题为：这篇新闻报道主要是关于什么的？出题点位置为首段首句。根据原文“One dog has been killed and multiple dogs have been injured by a snowmobile driver in what appears to be an intentional attack on competitors in the Iditarod Race in Alaska.”，可知在阿拉斯加的狗拉雪橇赛中，一雪橇车司机制造了一场故意袭击事件，造成了雪橇犬一死多伤。选项C）Attacks on some Iditarod race competitors（袭击了一些雪橇犬竞赛的竞争者），与原文信息一致。