The correct option is
A realistic yet interesting
"A character sketch is a description made for the purpose of guiding the writer on such assignments as introducing a particular character to the reader in such a way that both the writer and readers can have a quick overview of the character's attributes; including but not limited to physical appearance, idiosyncratic (individual) tendencies in different circumstances, state of mind as shaped by former experiences and how these will affect their future actions."Option A: This is the most appropriate, logical option. A character should, while being realistic, should also be interesting. It should engage the reader in a way that he or she wants to know more about this character. Hence option A is correct.
Option B: 'Realistic' and 'factual' have similar meanings. 'Yet' presents a contrast between two things, not similarities.
Option C: A character sketch should not be imaginative, but realistic. An imaginative character sketch would require action and plot, which are not a part of a character's sketch.
Option D: 'Descriptive' and 'concise' are two opposites (on extremes), and we can't include both aspects while writing a character sketch. It's either descriptive or concise.
Hence options B, C and D are wrong.