The elevations, in feet, of three cities are marked on the number line shown below.







The point 0 on the number line represents sea level. Which statement must be true?


A
City P and City Q are above sea level.

B
City Q and City R are below sea level.

C
City P is above sea level and City Q is below sea level.

D
City P is above sea level and City R is below sea level.