281: Where was the selection of suitable candidates for a particular job first started through competitive examinations?
(a) China
(b) Great Britain
(c) U.S.A.
(d) Germany
282: A class of animals known as Marsupials is a characteristic feature of
(a) Africa
(b) Australia
(c) South America
(d) South-East Asia
283: What would happen if phytoplankton of an ocean is completely destroyed for some reason?
1. The ocean as a carbon sink would be adversely affected.
2. The food chains in the ocean would be adversely affected.
3. The density of ocean water would drastically decrease.
Select the correct answer using the codes given below :
(a) 1 and 2 only
(b) 2 only
(c) 3 only
(d) 1, 2 and 3
284: Assertion (A): The main constituent of the Liquefied Petroleum Gas is methane.
Reason (R): Methane can be used directly for burning in homes and factories where it cab be supplied through pipelines.
(a) Both A and R are individually true and R is the correct explanation of A.
(b) Both A and R are individually true but R is not the correct explanation of A
(c) A is true but R is false.
(d) A is false but R is true.
285: Jaundice is caused due to the malfunctioning of:
(a) Kidney
(b) Liver
(c) Pancreas
(d) Stomach