Price Discrimination produced, increase, actually, quantity, efficiency

hinsafdar

In the Schweser notes, it explains that in a perfect price discrimination scenario, it could actually increase allocative efficiency, as a greater quantity could be produced.

I got a question wrong on a mock exam (7 City) because I chose that is increased effeciency (the answer was decreased). I guess we're to assume that it's not perfect price discrimination? In hindsight, of course that makes sense.