What is the mood of the excerpt? angry troubled lively rational

This question is missing the excerpt. I have found it online. It is the following:

Read the excerpt from "The Strange Case of Dr. Jekyll and Mr. Hyde":

Six o'clock struck on the bells of the church that was so conveniently near to Mr. Utterson's dwelling, and still he was digging at the problem. Hitherto it had touched him on the intellectual side alone; but now his imagination was engaged, or rather enslaved; and as he lay and tossed in the gross darkness of the night and the curtained room, Mr. Enfield's tale went by before his mind in a scroll of lighted pictures. He would be aware of the great field of lamps of a nocturnal city; then of the figure of a man walking swiftly; then of a child running from the doctor's . . .

The mood of the excerpt is:

B. troubled.

Explanation:

The adjective "troubled" is used to refer to someone who is anxious or worried, who is constantly thinking of a problem or issue. Thus, it is the best adjective to describe the mood of the excerpt we are analyzing here. Mr. Utterson is clearly thinking about something over and over again:

"and still he was digging at the problem."

He can barely think of or notice anything else. It is as if his mind is full, to the point where he cannot sleep:

"as he lay and tossed in the gross darkness of the night"

Explanation:

Believe in me