Why was the concern over global cooling replaced with a concern over global warming?
a.
The science community needed a cause to frighten the general population.
b.
Steady surface temperature increases were noted between the 1970’s and 90’s.
c.
Air pollution only became a concern in the 1980’s.
d.
Scientists observed severe ocean acidification.


Please select the best answer from the choices provided

A
B
C
D