The answer to this would be A.
This is because the numerators represent the the number of tomatoes and the denominators represent the amount of pints that are being made. The fraction on each side of the equal sign compares the number of tomatoes to the amount of pints. Therefore, the correct answer would be A. Hope I helped :)
The 3rd side would have to be at least 1 foot (4 minus 3) and no longer than 7 feet (4 plus 3).