Option 1 -> rejoicing: Being happy about poverty doesn't fit the negative consequence described in the sentence.
Option 2 -> fighting: Struggling against poverty would be a positive action, not something that prevents success.
Option 3 -> grumbling: Constantly complaining about poverty creates a negative mindset that hinders progress.
Option 4 -> ignoring: Ignoring poverty might actually help one move forward, not prevent success.
Hence, Option 3: grumbling -> Constant complaining and dwelling on one's poverty creates a victim mentality that prevents people from taking action toward success and happiness. A negative, complaint-focused attitude becomes a self-fulfilling prophecy that keeps people trapped in their circumstances -> correct