Determine whether the graph shows a positive correlation, a negative correlation, or no correlation. If there is a positive or negative correlation, describe its meaning in the situation. Sport Utility Vehicle Sales in the U. S., 1991-2001
Vehicles (millions)
A graph titled Sport Utility Vehicle Sales in the U S from 1991 to 2001 has year on the x-axis, and vehicles (millions) on the y-axis. Points trend in a positive line.

Year

Source: The World Almanac, 2003

a.
negative correlation; as time passes, SUV sales decrease.
b.
no correlation
c.
positive correlation; as time passes, the SUV sales decrease.
d.
positive correlation; as time passes, the SUV sales increase.