स्टीफन क्रैशेन के 'द्वितीय भाषा अधिग्रहण सिद्धांत' (Second Language Acquisition theory) के अनुसार, नई भाषा सीखने की प्रक्रिया में कितने चरण होते हैं?

According to Stephen Krashen's Affective Filter Hypothesis, learners with a ______ seek and receive more input, interact with confidence, and are more receptive to the input they receive.

Which psychologist proposed the view that language is acquired primarily through imitation, reinforcement, and operant conditioning?