In the context of Second Language Acquisition (SLA), what does Krashen’s 'Monitor Hypothesis' suggest?

1. ক
   Learners acquire language through comprehensible input
   
2. খ
   Learners use conscious knowledge to edit their output
   
3. গ
   Language learning is purely a subconscious process
   
4. ঘ
   Affective filters block language acquisition