It is believed that increasing amounts of greenhouse gases in the atmosphere will result in
a. higher average global temperatures
b. cooler average global temperatures
c. no changes in average global temperatures

"Belief" is not involved.  

Choice-A is the correct answer. Except that it's not "... will result in ...".  It's already happening.

The people who have been keeping records of temperatures at a thousand places around the world, for the past hundred years, do not "believe".  They know that average global temperatures are increasing, and have been increasing steadily for a couple of Centuries now.

Working from hypotheses, models, observations, and proven laws of nature, the global scientific community are convinced that increasing amounts of greenhouse gases in the atmosphere, driven by human activity, are the cause of the trend in average global temperatures.

Yes, you can find published researchers who aren't so sure, and who disagree with this conclusion.  The scientific community is never 100% unanimous.  There were reasonable investigators and scientific observers who disagreed with Galileo, Newton, Faraday, Maxwell, Hawking and Einstein, in their time.  

But the voices that dispute human-caused climate change in the form of global warming are few, and they're becoming fewer as time goes on. Today, their reputation sits just a few notches above that of the Flat-Earthers, and it's continuing to sag further.

If we are to do what has to be done, in time to bring about the needed effect, it can't sag fast enough.

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia