The correct answer is Antimicrobial resistance. Key Points Antimicrobial resistance is the ability of microorganisms to grow despite being exposed to antimicrobial agents. It is the resistance acquired by any microorganism against antimicrobial drugs that are used to treat infections. Increased use of antibiotics is one of the main causes of antimicrobial resistance. As we increase the use of antibiotics few bacteria become resistant. Antimicrobial resistance occurs naturally over time, usually through genetic changes. They are found in people, animals, food, plants and the environment (in water, soil and air). It occurs when bacteria, viruses, fungi and parasites change over time and no longer respond to medicines making infections harder to treat and increasing the risk of disease spread, severe illness and death. As a result of drug resistance, antibiotics and other antimicrobial medicines become ineffective and infections become increasingly difficult or impossible to treat. World Health Organisation has declared Antimicrobial resistance as one of the top 10 global public health threats facing humanity.