How to mock GetAnswersAsync function in Custom question answering service

Question

I have migrated from QNA maker to Custom question answering service for the bot project.

Now, I want to mock the function ,

Task<Response> GetAnswersAsync(int qnaId, QuestionAnsweringProject project, AnswersOptions options = null, CancellationToken cancellationToken = default);

for unit test.

Can anyone help on this