John McCarthy is regarded as the father of Artificial Intelligence (AI). He coined the term “Artificial Intelligence” in 1956 during the Dartmouth Conference, which is considered the founding event of AI as a research field. McCarthy also developed the LISP programming language, one of the earliest languages used for AI programming. His contributions laid the foundation for modern AI research, machine learning, and robotics.

Other options (for context)

• Charles Babbage: Known as the “Father of the Computer” for designing the Analytical Engine.
• Lee De Forest: Invented the triode vacuum tube, which advanced early electronics.
• J. P. Eckert: Co-inventor of ENIAC, one of the first electronic general-purpose computers.

Marble is not an element; it is a metamorphic rock composed primarily of calcium carbonate (CaCO₃). It forms when limestone is subjected to high pressure and temperature, causing recrystallization. Being a compound and mixture of minerals, marble does not consist of a single type of atom, unlike elements.

Other options (for context)

• Oxygen (O₂): A chemical element essential for respiration and combustion.
• Nitrogen (N₂): A chemical element that makes up about 78% of Earth’s atmosphere.
• Hydrogen (H₂): The lightest chemical element and the main component of stars.

Explanation: CNG stands for Compressed Natural Gas. It is an eco-friendly fuel made primarily of methane (CH₄) and is used as an alternative to petrol and diesel. CNG burns cleanly, producing fewer pollutants and helping reduce air pollution.

Explanation: Dehydration happens when the body loses excessive water through sweating, vomiting, diarrhea, or inadequate fluid intake. It disturbs the balance of electrolytes and reduces blood volume, leading to symptoms such as thirst, dry mouth, fatigue, and dizziness. To prevent dehydration, oral rehydration solutions (ORS) or adequate water intake are essential.

Red light has the longest wavelength among visible colours, approximately 620–750 nanometers. Due to its longer wavelength, red light is scattered the least, which is why it is used in traffic signals and as warning lights for better visibility over long distances.

• Blue and Green: Shorter wavelengths, scattered more easily.
• Yellow: Intermediate wavelength between red and green.

Explanation: When salt is added to pure water, its boiling point increases. This phenomenon is known as boiling point elevation, a colligative property. The presence of dissolved salt particles reduces the vapor pressure of water, requiring a higher temperature for it to boil.

Nitrous oxide (N₂O) is an anaesthetic gas, commonly known as laughing gas. It is used in dentistry and minor surgeries to induce mild anesthesia and relaxation. It acts quickly and wears off rapidly, making it safe for short medical procedures.

• Nitrogen dioxide: A toxic air pollutant, not used as anesthesia.
• Nitric oxide: A signaling molecule in the body, not an anesthetic.
• Nitrogen: An inert gas, does not induce anesthesia.