Explanation

Smallpox was eradicated in Pakistan in 1980, along with the rest of the world, as declared by the World Health Organization (WHO).

Explanation

• Muscular degeneration, also known as Age-related Macular Degeneration (AMD).
• It is a disease that affects the macula, the part of the retina responsible for central vision.
• It causes vision loss in the central field of vision, making everyday tasks like reading, driving, and recognizing faces challenging.

Explanation

The depletion of the Earth's ozone layer allows more harmful ultraviolet (UV) radiation from the sun to reach the Earth's surface, leading to:

• Increased risk of skin cancer and cataracts in humans
• Damage to crops and marine life
• Disruption of ecosystems

Explanation

Glaucoma is caused by an increase in pressure within the eyeball, specifically in the fluid pressure inside the eye.

This increased pressure can damage the optic nerve and lead to vision loss if left untreated.

Explanation

• Erosion is the process of wearing away or removal of topsoil, rock, or other materials from the Earth's surface by natural forces such as wind, water, or ice.
• It is a natural process that shapes the landscape and can lead to the loss of fertile soil, landslides, and other geological changes.

Explanation

• Chlorine is commonly used for disinfection of water, as it is effective against a wide range of bacteria, viruses, and other microorganisms.
• Chlorine is often added to drinking water as a disinfectant, and it is also used to disinfect swimming pools and other water sources.

Explanation

Indigo is a large genus (Indigofera) of plants in the family Fabaceae, which includes trees, shrubs, and herbs. 

Explanation

• Eugenics is a controversial and outdated field of study that aimed to improve the human race by selectively breeding individuals with desired traits and characteristics.
• It involved the study of heredity and the manipulation of genetic components to alter human traits, often with the goal of creating a perceived "superior" race or population.

Explanation

• Nuclear energy is a method of harnessing the energy released from the splitting of atomic nuclei (a process called nuclear fission) to generate electricity.
• The main purpose of nuclear energy is to provide a clean and reliable alternative source of energy, reducing dependence on fossil fuels and mitigating climate change.

Explanation

• Hematology is a subspecialty of pathology that specifically deals with diseases related to blood and blood-forming organs.
• Hematologists diagnose and treat blood disorders such as anemia, bleeding disorders, and blood cancers like leukemia.