A car salesman recorded the number of people who purchased a new car and the car's color. He then created the following bar graph:

Which of the following statements best compares the heights of the bars of the bar graph?
There are more people who purchased a red car than white and black cars combined.
There are more people who purchased a silver car than white and black cars combined.
There are twice as many people who purchased a red car than a black car.
There are 3 times as many people who purchased a black car than a silver car.