Enthusiasm
(hope this works)
The correct answer is the last option - MRS. HALE (stiffly).
It is the only stage direction among the choices above which shows that the character is supposed to depict some kind of emotion (in this case, a stiff emotion). The other options are just examples of what the character should do and behave like, but they don't mention feelings.
Answer: hi! i believe the answer is D ;))
Explanation:
It has a positive connotation, suggesting the astrophysicist's long lasting and innocent fascination with the universe.
