Final answer:
C. 520 out of 800 students ride the bus.
Step-by-step explanation:
To find the number of students who ride the bus, start by calculating 65% of the total number of students at North High School. To do this, multiply the total number of students by 65% or 0.65, which represents the decimal form of 65%.
So, 65% of 800 students is calculated as:

Therefore, 520 out of the 800 students at North High School ride the bus. The 65% figure represents the portion or fraction of students who utilize the school bus as their mode of transportation. This calculation shows that more than half of the student population relies on the bus for commuting to and from school. Understanding this percentage helps in gauging the school's transportation needs and capacity for accommodating student ridership.