Here's how the Pony Express worked. A young rider would grab a mailbag then jump on a horse and ride for ten miles at top
speed. Then he would jump on a fresh horse and keep going. He would change horses seven times, and then he would pass the
mailbag to another rider, who would keep on riding another seven horses for another seventy miles until he reached the next rider!
The structure of the selection above can best be described as
ОА.
sequence.
ОВ.
classification
OC
compare and contrast.
OD
cause and effect