Inquisitor with known highest Jedi Rank:
Grand Inquisitor - Former Jedi Knight
Trilla - Former Padawan
Reva - Former Youngling
All other Inquisitors Jedi status are unknown if they were a youngling, padawan, or knight.
So, you can't realy say "most" because only one didn't have a rank higher than youngling. You can say there were likely younglings given their ages, but they could have been Padawans.