As used in the last sentence, the phrase "in short' means ______.

A．It shows that modem humans lived in the Arctic more than 3,000 years ago.
B．It shows that Neanderthals lived in the Arctic more than 3,000 years ago.
C．It shows the oldest documented evidence for human presence at such high latitude.
D．It shows human could use tools 30,000 years ago.

A．Moderate temperature, relatively dry and ice -free.
B．Extremely cold, relatively dry and ice- free.
C．Extremely cold, plenty of raining and ice- free.
D．Extremely cold, relatively dry and ice frosted.