Answer:
D results from studies conducted on birds and other animals.
i dont know bro ask the teacher Explanation:
The primary purpose of these stage directions (with the gallantry of a young politician) is to indicate a character's tone of voice.
Given that he is referring to the ladies, he has to change the tone of his voice a bit to appeal to them more. He cannot speak in a manly voice which he would normally use while speaking to other men, but rather appear more suave and gentleman-like.