45 The qualifying words easy, simple, efficient, and effective are used, in the text (part 3), to refer to: psychological principles. scientific ...

45 The qualifying words easy, simple, efficient, and effective are used, in the text (part 3), to refer to:

psychological principles.
scientific methods.
educational technology.
the teaching/learning process.
A) psychological principles.
B) scientific methods.
C) educational technology.
D) the teaching/learning process.