Grade inflation is a problem. I think most people are already convinced of that, so I’ll skip to the solution.

It’s simple. Percentiles. People no longer receive scores based directly on how many answers they got right. These scores are converted into percentiles. Percentiles are the number “what percentage of people did you score better than”. So the subjects are divided equally into 100 groups.

It is a simple and old thing, but it does solve the major problems with exams which are intractable under normal systems, and are today costing examining bodies years of effort to try to deal with.