______ language acquisition device (LAD)

问题：

______ language acquisition device (LAD)
2) ______ stimulus and response
3) ______ the discourse theory
4) ______ acquisition and learning
5) ______ the input hypothesis
a) The former refers to the subconscious process leading to the development of "competence"; the latter refers to conscious study and knowledge of grammatical rules.
b) A sort of mechanism or device which contains the capacity to acquire one’ s first language.
c) It assumes that humans acquire language in only one way--by understanding messages, or by receiving "comprehensible input".
d) It believes there is little difference between the first language acquisition process and the process of second language acquisition--only through communication discourses.
e) The former serves to elicit behaviour; the latter is triggered by the former.