General Knowledge

Geriatrics is the branch of medicine that focuses on the health and care of elderly people, making option D the correct answer. Obstetrics deals with childbirth, pediatrics with children, and calisthenics refers to physical exercises.

A quadrillion is equal to 1,000,000,000,000,000, which is the number 1 followed by 15 zeros. This is based on the short scale numbering system used in the US and most English-speaking countries. Therefore, the correct answer is option A: 15 zeros.

Euclid is known as the Father of Geometry because of his influential work 'Elements,' which systematically compiled and organized the knowledge of geometry in ancient times.

Options A, B, and D refer to actual water sources or bodies of water, whereas option C, 'Mirage,' is an optical illusion and not a real water source. Therefore, 'Mirage' does not belong to the group.

CAT, DOG, and TIGER are all carnivorous mammals, while ELEPHANT is an herbivorous mammal. Therefore, ELEPHANT does not belong to the group based on diet and species type.

Option B, 'Japanian', is not a correct demonym for people from Japan; the correct term is 'Japanese'. All other options are correctly formed demonyms for their respective countries, so 'Japanian' does not belong in the group.

Option D is the odd one out because Australia does not use the Pound as its currency; it uses the Australian Dollar. The other countries listed use the currencies mentioned correctly: Pakistan uses Rupee, America uses Dollar, and Kuwait uses Dinar.

Among the options, 'Regiment' is a military unit, while 'Lieutenant', 'Colonel', and 'Major' are military ranks. Therefore, 'Regiment' does not belong to the group of ranks.

Among the options, Museum, Exhibition, and Botanical park are places where items or specimens are displayed for public viewing, whereas Auction is an event where items are sold to the highest bidder, making it the odd one out.

Options A, B, and C are all actions involving communication or consumption, while D (Plank) is an exercise or position, making it the odd one out.