Answer:
C). Beyond the realm of reality and/or sanity .
Step-by-step explanation:
As per the question, the implied or intended meaning of the word 'fanciful' would be 'beyond the realm of reality and/or sanity' as reflected by the context cues provided by the author. The literal meaning of the word is 'something imaginative, fantastic, or unreal' which connotes(as per the passage) that Jekyll became quite 'unrealistic or capricious.' He displays an 'overimaginative and impractical behavior' which is reflected through his 'going wrong in mind, unscientific, and estranged actions.' Thus, option C is the correct answer.