How common is a must-pass-final requirement? For a course with a final exam, is it more common to: (a) require that the final exam be passed to pass the course, or (b) allow for a student to fail the final exam and still pass the course? 

How could we estimate the relative proportion of the two policies? If someone argued that case (a) was "rare" in higher education, how could we respond?

Edit: Consider restricting to mathematics classes at American universities, with a comprehensive final exam, if that's clarifying.
If someone argued that case (a) was "rare" in higher education, respond by:


asking for the data they used to come to that conclusion
determine if sample size is large enough to make any reliable conclusions
determine what 'rare' means
measure if the number of pass/fail final exams is greater than or less than the rare threshold


If they don't have data, then respond by saying that their personal experiences probably do not represent a national average.