Definition: You are given a passage. You need to construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) its answer is the whole paragraph. Avoid creating questions that can be answered correctly without actually understanding the paragraph.
Input: Walter Payton is my personal favorite. Who knows how good he could have been if he would have played on some decent teams earlier in his career.

However some others that might be metioned are:

Jim Brown - Excellent choice, can't go wrong with a Brown ;)

and

Barry Sanders - Best moves ever, also played on sorry teams.

One thing that works against Brown and Sanders is that they retired early, instead of stretching their careers out and maximizing their rushing yardage.

As far as a running back who flashed brilliantly for a short time.....no one burned brighter for shorter than Earl Campbell.....he was a horse....
Output:
Who is the best running back of all time?