OG16 SC78. The 32 species that make up the dolphin family are closely related to whales and in fact include the animal known as as killer whale, which can grow to be 30 feet long and is famous for its aggressive hunting pods.
(B) include the animal known as the killer whale, growing up to 30 feet long and being
原句是答案，我纠结的是B选项用分词为什么不可以。官方解释原文“Changing the verb to the participal growing introduces ambiguity, because it could refer back to the subject of the sentence(32 species).”
SC86. To map Earth's interior, geologists use a network of seismometers to chart seismic waves that originate in the earth's crust and ricochet around its interior, most rapidly traveling through cold, dense regions and slower through hotter rocks.
(B) interior, which travel most rapidly through cold, dense regions, and more slowly
(C) interior, traveling most rapidly through cold, dense regions and more slowly
答案是C。 解析原文“The referent of the relative pronoun which is unclear.” 他指的unclear是which还能指代另外的名词，可是按照就近和逻辑，which最可能修饰 seismic waves没错呀。