To solve for the number of people who died in the attacks of September 11, 2001, let's look at the values provided in the options:
1. 2,000
2. 2,500
3. 3,000
4. 3,500
According to historical records, the estimated number of deaths resulting from the attacks on September 11, 2001, is approximately 3,000.
Therefore, the correct answer, indicating the approximate number of people who died in the attacks, is:
[tex]\[
\boxed{3,000}
\][/tex]
So the correct selection from the given options is 3,000.
