Explanation: PROLOG (Programming in Logic) is a high-level programming language widely used in the field of Artificial Intelligence (AI) and computational linguistics. It is based on formal logic and is especially useful for solving problems involving pattern matching, rule-based reasoning, and natural language processing.

Explanation: A transformer is an electrical device used to increase (step-up) or decrease (step-down) the voltage of alternating current (A.C.). It works on the principle of electromagnetic induction and functions only with A.C., not with D.C. A transformer consists of two coils—primary and secondary—wound around a soft iron core. The voltage ratio between these coils depends on the number of turns in each winding. Transformers are used in power transmission, distribution, and electronic devices to regulate voltage levels efficiently.

Explanation: A Local Area Network (LAN) is a network of computers and peripherals confined to a small geographical area, such as a home, school, or office building. It enables resource sharing, file transfer, and communication among connected devices within the limited range.

Explanation: The Sun is seen a few minutes before actual sunrise and after actual sunset due to the refraction of light by the Earth's atmosphere. The atmosphere bends the Sun’s rays towards the Earth, making the Sun appear slightly above the horizon even when it is below it.

Explanation: Photosynthesis is the process by which green plants, algae, and some bacteria use sunlight to convert carbon dioxide (CO₂) and water (H₂O) into glucose (C₆H₁₂O₆) and oxygen (O₂). This process takes place in the chloroplasts of plant cells, which contain the green pigment chlorophyll that captures solar energy.

Chemical Equation:

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

Thus, plants are known as autotrophs because they produce their own food using light energy — a process vital for sustaining all life on Earth.

Explanation: A concave mirror can produce an image that is larger than the object when the object is placed between the mirror’s pole and its focal point. This property makes concave mirrors useful in applications like shaving mirrors and makeup mirrors, where magnified images are needed.

A Hygrometer is an instrument used to measure the humidity (moisture content) in the atmosphere. It helps determine the percentage of water vapor present in the air, which is essential for weather forecasting, climate studies, and maintaining controlled environments in industries or laboratories. Some common types include the dry and wet bulb hygrometer and the digital hygrometer.

Other options (for context)

• Barometer: Used to measure atmospheric pressure.
• Anemometer: Used to measure wind speed.
• Thermometer: Used to measure temperature.

Explanation: A light year is a unit used to measure stellar or astronomical distances. It is defined as the distance that light travels in one year in a vacuum. Since light moves at a speed of about 3 × 10⁸ m/s, one light year equals approximately 9.46 × 10¹² km. It is commonly used to express distances between stars and galaxies because these distances are too large to be measured in kilometers or miles.

Explanation: The term LASER stands for Light Amplification by Stimulated Emission of Radiation. A laser produces a highly coherent, monochromatic, and intense beam of light by amplifying light through the process of stimulated emission. In this process, atoms or molecules in an excited state emit photons in phase with incoming photons, resulting in a strong, directed beam. Lasers are widely used in medicine, communication, industry, defense, and scientific research.

Explanation: The term "Ozone hole" does not mean an actual hole but refers to a significant decrease in the thickness of the ozone layer in the Earth's stratosphere. This thinning occurs mainly over the Antarctic region during spring (September–November) due to chemical reactions involving chlorofluorocarbons (CFCs) and other ozone-depleting substances. These chemicals release chlorine and bromine atoms, which destroy ozone (O₃) molecules. The thinning allows more harmful ultraviolet (UV) radiation to reach the Earth's surface, causing health and environmental hazards.