IIT-Roorkee has conducted research indicating that emissions from vehicles in Delhi have increased close to ____ times between 1991 and 2011.

a. 2

b. 3

c. 4

d. 5

ANSWER: 3

Explanation:

An 8 year study conducted by IIT Roorkee, University of Minnesota and University of Surrey have shown that emissions from vehicles in Delhi rose up to 3 times between 1991 and 2011. This is projected to rise by 19 times by 2020. Private vehicles emissions have increased by 2 to 12 times in 2011 and 2 to 16 times in 2015 over 1991 levels.