Which theme of sir arthur conan doyle’s “the adventure of the speckled band” is expressed in this excerpt from the story?

"were there gipsies in the plantation at the time? "

"yes, there are nearly always some there."

"ah, and what did you gather from this allusion to a band—a speckled band? "

"sometimes i have thought that it was merely the wild talk of delirium, sometimes that it may have referred to some band of people, perhaps to these very gipsies in the plantation. i do not know whether the spotted handkerchiefs which so many of them wear over their heads might have suggested the strange adjective which she used."

holmes shook his head like a man who is far from being satisfied.

a.
the importance of proof and logic
b.
the dangers of jumping to conclusions
c.
good versus evil
d.
england’s fascination with the east