10755 - Part D (Page 179) Test:15 - ______ is that there is a risk of heart attack for the elderly.

______ is that there is a risk of heart attack for the elderly.
If there is one important drawback of aerobics.
There is one important drawback of aerobics
One important drawback of aerobics
It is one important drawback of aerobics
Elementary Grammar Exercises A1
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