Final answer:
Teachers assign grades based on student performance. Grade inflation is a concern where the correspondence between letter grades and achievements has changed over time. Effort, quality of work, and student evaluations may influence grades.
Step-by-step explanation:
Teachers assign students' letter grades based on their performances. Commonly, these grades are determined using a bell curve. Grade inflation is a growing concern, where the correspondence between letter grades and achievements has been changing in a downward direction over time. What used to be considered an average grade now often earns a student a higher grade. Factors such as effort, quality of work, and student evaluations may influence how grades are assigned. Additionally, grade inflation may occur due to the pressure for positive course evaluations or the desire to improve admissions and hiring prospects for students.