Correct option is A
The term ‘comprehensible input’ in language learning means providing language input to the children which is one level above the learner's language. This concept, introduced by Stephen Krashen, suggests that language acquisition occurs when learners are exposed to language that is slightly beyond their current level of proficiency but still understandable. This input should contain structures that are new to the learner, providing a challenge but still being comprehensible, thereby facilitating language acquisition.