题目内容：
根据以下材料，回答题。
A．This mountain rises 1，532 feet，making it the highest mountain on the Atlantic seaboard.
B．It is split almost in half by Somes Sound，a deep and narrow stretch of water，seven miles long.
C．It also lies in a major bird migration lane and is a resting spot for many birds.
D．The term comes from the activity of the ice age.
E．Mt. Desert Island is one of the most famous of all the islands left behind by the glacier.
F．The wealthy residents of Mr. Desert Island selfishly kept it to themselves.
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