What was the question posed by Molina that began to put the
pieces together?

Questioned what might happen if CFCs rose into higher altitudes and stayed there for a longer period of time.

Explanation:

Mario Molina noticed that Chlorofluorocarbons (CFCs) did not breakdown in lower atmospheric conditions unlike other chemicals released into the air. He observed that CHCs rose to higher altitudes where solar radiation were stronger.Through this observation, he questioned what might happen if CFCs rose into higher altitudes and stayed there for a longer period of time. This question led to the finding that the chlorine present in CFCs depleted the ozone layer which protects the earth from direct solar radiation.It helped in understanding the affects of CFCs to the environment and ozone layer which subsequently led to the ban and limitation on the use of CFCs altogether.

Answer dot(3) is most used;

True is the answer. hthhth