506: Which one of the following pairs of cities has recently been connected through a 6-lane express way ?
(a) Ahmedabad : Vadodara
(b) Dhaka : Chittagong
(c) Islamabad : Lahore
(d) Mumbai : Pune
507: Which one of the following is known as the Coffee portĀ of the world ?
(a) Sao Paulo
(b) Santos
(c) Rio de Janeiro
(d) Buenos Aires
508: The first metal used by the man was:
(a) Iron
(b) Copper
(c) Aluminium
(d) Gold
509: Rennin and lactase, the enzymes required to digest milk, disappear in the human body by the age of
(a) two
(b) three
(c) five
(d) eight
510: Karl Marx explained the process of class struggle with the help of which one of the following theories?
(a) Dialectical materialism
(b) Empirical liberalism
(c) Existentialism
(d) Darwin's theory of evolution