单选题 Two buses are 515 miles apart. At 9:30 a. m., they start traveling toward each other at rates of 48 and 55 miles per hour. At what time will they pass each other?
A. 1:30 p.m. B. 2:00 p.m.
C. 2:30 p.m. D. 3:00 p.m.
E. 3:30 p. m.