Answer:
Summarizing an essay can help the reader to identify the important content and organize it in a way that makes it easier to understand.
Explanation:
A subject in grammar is the first part in a sentence about which the second part, the predicate, tells something.
I would go with option d)
Gehrig<span> was known as the </span>Iron Horse<span> because he established a record for the number of consecutive games played by a professional baseball player, appearing in 2130 consecutive games from 1925 to 1939. His record was broken in 1995 by Cal Ripkin, Jr., of the Baltimore Orioles.</span>
