Performance Group A
All multi-engine turbo-jet and all multi-engine turbo-prop with more than 9 seats or with MTOW > 5,700kg
Performance Group B
All propeller driven aircraft with less than 9 seats or MTOW
< 5,700kg
Performance Group C
All piston engine aircraft with more than 9 seats or MTOW > 5,700kg
Group C is not included in the ATPL or CPL theory exams.
Hope this helps