C) They feed primarily on only a few kinds of krill in the Antarctic Polar Front.

C) 它们主要以南极极地前缘的几种磷虾为食。

As the ocean warms, a body of water called the Antarctic Polar Front — an upward movement of nutrient-rich sea that supports a huge abundance of marine life — is being pushed further south.

随着海水变暖，一片名为南极极区锋面的水域，由营养丰富的海水上升而形成，栖息着大量的海洋生物，该峰面正在不断向南移动。