A sentence has been given with a blank to be filled with an appropriate word.…

Answer: challenges

Key idea: The blank follows the phrase “one of the biggest,” so the correct word should be a noun that means a major problem or difficulty faced by the country.

• “challenges” fits because it means problems or difficulties; the sentence becomes: Waste management is one of the biggest challenges for the country.

• “compromise” means a settlement or mutual concession, which does not express a problem.

• “sacrifices” means giving up something, not describing a problem faced by the country.

• “lead” does not convey the sense of a major problem or difficulty in this context.

Conclusion: “challenges” is the best fit because it correctly conveys that waste management is a significant problem the country must address.