Answer:
The group that best represents the population from which the student should take a random sample to get the best results for the survey is option A: All school teachers.
In the given scenario, the student wants to know the preference of all the teachers in the entire school and therefore, the population of interest is all school teachers. The best way to obtain a representative sample is to take a simple random sample from the population of interest. Option A provides the best representation of the population of interest, as it includes all the teachers in the school.
Option B, C, and D may not be representative of the population of interest. Option B includes only students on the football team, which may not be representative of all school teachers. Option C includes only boys in each grade, which excludes girls and may not be representative of all school teachers. Option D includes all students in each grade, which again may not be representative of all school teachers.