Day-616 | Daily MCQs | UPSC Prelims | SCIENCE AND TECHNOLOGY

Answer. A
Explanation:
Statement 1 is incorrect: Rat-hole mining involves digging of very small tunnels, usually only 3-4 feet deep, in which workers, more often children, enter and extract coal. It is practiced in the Northeastern States of India because the coal seams are thin and the coal quality is bad: having high sulphur content. These factors make open mining an unfeasible option in such regions.
Statement 2 is incorrect: Since rat-hole mining is illegal, it is practiced behind closed doors. The water in the Kopili River (flows through Meghalaya and Assam) has turned acidic (i.e. the pH levels in the river have dropped). The entire roadsides in and around mining areas are for piling of coal. This is a major source of air, water and soil pollution.
Statement 3 is correct: The National Green Tribunal (NGT) has banned rat-hole mining in 2014, and retained the ban in 2015. The ban was on grounds of the practice being unscientific and unsafe for workers.

Answer: B
Explanation
Pair 1 is correctly matched: Artemis programme is a series of missions planned by NASA with an aim to establish a permanent base on the Moon. The lunar base will eventually be utilised as a launching pad for various manned Mars missions in future.
Pair 2 is incorrectly matched: It is the SLIM mission, which is a small-scale exploration lander designed for pinpoint landings on the Moon’s surface. Both the missions (XRISM and SLIM) have been initiated by the Japanese Space Agency (JAXA). The X-Ray Imaging and Spectroscopy Mission (XRISM) is an X-ray space telescope mission to provide breakthroughs in the study of structure formation of the universe and outflows from galaxy nuclei.
Pair 3 is correctly matched: Euclid mission is a space telescope designed to explore the composition and evolution of the dark Universe. It is a mission by the European Space Agency (ESA). Euclid will explore how the Universe has expanded and how structure has formed over cosmic history, revealing more about the role of gravity and the nature of dark energy and dark matter.

Answer: B
Explanation
Statement 1 is incorrect: It is Vitamin C which helps in the synthesis of collagen. Collagen is the primary building block of body’s skin, muscles, bones, tendons and ligaments, and other connective tissues. It’s also found in our organs, blood vessels and intestinal lining.
Statement 2 is correct: Biotin is also known as Vitamin H. It is a water-soluble vitamin that plays a role in the growth of hair. Along with this it also helps in the metabolism of fats, carbohydrates, and amino acids. It was initially called “H” from the German word “Haar und Haut,” meaning hair and skin.
Statement 3 is correct: Basking in the sun isn’t just for relaxation; it triggers the skin to produce a vital vitamin known as Vitamin D. The sun’s energy turns a chemical in the skin into vitamin D3, which is carried to the liver and then to kidneys to transform it to active vitamin D.

Answer: C
Explanation
Statement 1 is correct: A core is a physical component of the CPU that can execute instructions. Thus, it is a hardware-based processing unit within a CPU. A CPU performance will depend upon the number of cores on the machine and the speed at which the individual cores can execute instructions.
Statement 2 is correct: Thread is a single sequential flow of control in a program that allows multiple activities within a single process. Thus, it is the software-based instruction. In other words, a single thread is like one command that runs at a time.

Answer: A
Explanation
Machine Learning and Deep Learning are the two main concepts of Data Science and the subsets of Artificial Intelligence.
Machine Learning allows the computers to learn from the experiences by its own, use statistical methods to improve the performance and predict the output without being explicitly programmed.
Deep Learning is inspired by the functionality of human brain cells, which are called neurons, and leads to the concept of artificial neural networks. It is also called a deep neural network or deep neural learning.
● Statement 1 is CORRECT: Machine Learning algorithm is data driven. It follows a structured format for solving problems and thus is mainly employed for simpler tasks like predicting customer choice on e-commerce site. But, Deep Learning mimics complex neural schemas of human brain. It is adept at solving complex problems which require parallel processing.
● Statement 2 is INCORRECT: Deep Learning is a subset of Machine Learning. Deep Learning is a special case of machine learning in which each step is checked in a more elaborated manner.