Choose the most appropriate option to fill in blank no. 5.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. intricate.
The passage describes singing as an art that requires "systematic, prolonged, and strict training," implying that it is complex and requires a high level of refinement.
The word "intricate" means something that is very detailed and complex, fitting this description perfectly.
The other options don't match the context.