Answer the Question. -A Teacher Wants to Determine the Effect of Time of of Time

Answer the question.
-A teacher wants to determine the effect of time of bus riding on grades. Which sample might be affected by the
Personal interest of the reporters?

A) The report of GPA and bus riding time of all students at two tables in the school cafeteria
B) The report of GPA and bus riding time of all the students on one bus route
C) A sample of the records of 15 students eligible to ride the bus as determined by distance from school and another sample of 15 students not eligible to ride the bus
D) A sample of 15 records of students who ride the bus and 15 who do not ride the bus