Possible points for the world faces many global challenges
• The gap between the rich and the poor
• Environmental issues; oceans, air pollution and so on
• Religious conflicts
• Nuclear and/or chemical warfare
• The world faces many global challenges in form of various health issues – for example, decreasing efficacy of antibiotics
• Extinction of species
• Population growth
• Cyberattacks
• Illiteracy
• Tensions between developed and less developed countries/regions
• The drugs’ trade
• Migration
The question asks for one challenge to be identified. This challenge should be clearly stated but that does NOT preclude mention of related matters. The list of challenges cited above is not exhaustive and there may be other equally valid examples used in the essay.