Anaemia is caused due to a deficiency of iron in the body. Iron is an essential component of hemoglobin, the protein in red blood cells that carries oxygen. When the body lacks sufficient iron, it produces fewer and smaller red blood cells, leading to symptoms such as fatigue, weakness, dizziness, and pale skin. This condition is known as Iron-Deficiency Anaemia.

Other options (for context)

• Iodine: Its deficiency causes goitre, not anaemia.
• Vitamin: Certain vitamins like B₁₂ and folic acid deficiency can cause anaemia, but the most common cause is lack of iron.
• None of these: Incorrect — iron deficiency is the main cause of anaemia.

Explanation: Groundnut (Arachis hypogaea) is a leguminous plant that exhibits geocarpy — after fertilization a downward-growing peg pushes the fertilized ovary into the soil and the pod (the fruit) matures below ground. Potato, carrot and onion are underground plant parts but are respectively a tuber (stem), root and bulb — not fruits.

Explanation: The speed of light is maximum in a vacuum (approximately 3 × 10⁸ m/s) and decreases as it passes through denser media. Among the given options — vacuum, air, water, and glass — light travels slowest in glass because glass has the highest refractive index (around 1.5). The greater the refractive index, the slower the light travels. This slowing down of light causes refraction, or bending of light, when it passes from one medium to another.

Explanation: Execution time is the period during which a job or program is actively processed by the computer’s CPU. It refers to the actual time taken to execute instructions, excluding waiting or idle times such as input/output delays or queue time.

Explanation: LCD stands for Liquid Crystal Display. It is a flat-panel display technology commonly used in televisions, computer monitors, calculators, and smartphones. LCDs use liquid crystals that modulate light to produce images when an electric current is applied.

Explanation: Every computer connected to the Internet is identified by a unique numerical label called an IP Address (Internet Protocol Address). It consists of four numeric parts separated by dots (e.g., 192.168.1.1) and is used to locate and communicate with devices over the network.

Explanation: The Olive Ridley turtle (Lepidochelys olivacea) is the smallest and most abundant species of sea turtle found primarily in warm and tropical waters, including the Indian Ocean. It is named for the olive color of its shell. These turtles are famous for their unique mass nesting phenomenon known as “arribada”, where thousands of females come ashore simultaneously to lay eggs. In India, large nesting sites are found along the coast of Odisha, especially at Gahirmatha Beach and the Rushikulya River mouth.