I. High birth rate and high immigration rate
II. Low birth rate and high immigration rate
III. Low mortality rate and low emigration rate
IV. High mortality rate and high emigration rate.
A. II and III
B. I and III
C. I and IV
D. I and II
Correct Answer:
Option B = I and III
Explanation
Low mortality rate, high birth rate, high immigration rate and low emigration rate are causes for rapid over-crowding.