Communicative Language Teaching in language stresses on giving opportunities to learners to participate in a purposeful talk in classroom as it promotes :

Correct option is D

to improve their conversational skill in the target language.
Communicative Language Teaching (CLT) emphasizes the importance of providing learners with opportunities to use the language in real-world situations. This includes opportunities to talk, listen, read, and write. CLT helps learners to develop their conversational skills in the target language by providing them with practice using the language in a variety of contexts.