The correct way to punctuate is seen in b:
<span>To whom it may concern:
</span>
In formal settings and when you don't know the exact identity of the person a dresses it is usual to use a colon in this situation.
Not 100 percent sure but i think it is <span>b.they represent something great</span>
In Of Plimoth Plantation the characteristic of the authors writing style that is most evident would be "<span>Emotional Understatement" since the issue at hand is of course more serious. </span>
