Hungarian Author Laszlo Polgar Devoted Enormous Time and Effort to Teach

Hungarian author Laszlo Polgar devoted enormous time and effort to teach his three daughters chess. What was he attempting to demonstrate?

A) that expertise is something people are born with
B) that expertise is possible in almost anyone, given sufficient effort
C) that spatial skills in females are better than spatial skills in males
D) that massed practice leads to faster learning than spaced practice