The early "school" or approach to psychology called behaviorism emphasized which of the following ideas?
the scientific study of mental processes in humans and anim
the scientific study of the cognitive process involved in human and animal intelligence
the scientific study of observable behaviors rather than mental processes
the scientific study of how associations are formed between mental events and overt behaviors

John B. Watson is considered one of the fathers of the school of behaviorism in psychology, he introduced this concept in a publication made in 1924.

According to behaviorism, psychology should focus in measurable and observable data instead of emotions and ideas that couldn't be observed and measured.

The aim of behaviorism was to make psychology an objective science that would focus on hard data and observable behaviors, the behaviorists considered this approach as a revolutionary one.

Therefore, we can say that the school of behaviorism emphasized the idea of the scientific study of observable behaviors rather than mental processes.

Note: All the other options given have to do with mental processes and therefore, non observable ones, thus, they can not be the correct answer to this question