Arnold Schwarzenegger Lost in Translation Over Question About Son Joseph Baena

Arnold Schwarzenegger was more than happy to open up about son Joseph Baena's future prospects -- the snag ... he told us in German.

We got Arnold leaving Caffe Roma Monday in Bev Hills, and we wanted to know if Joseph -- who has stellar grades at Pepperdine and looks like a young Arnold -- has what it takes to become a movie star or politician.

The Terminator answered in his native tongue. Translation .... "You always ask me questions that I can't answer."

Verstanden.