What is the best reason for the scientific community to accept a theory?
the theory is supported by all the available observations and data.
an award-winning scientist proposed the theory.
the majority of the general public agrees with the theory.
the theory contradicts an older theory.

The best reason for the scientific community to accept a theory is this: THE THEORY IS SUPPORTED BY ALL THE AVAILABLE OBSERVATION AND DATA.

Science is a dynamic subject, scientific investigations are always on going and new discoveries are made regularly. For a particular discovery to be accepted by the scientific community, such a discovery must have been tested several times by different scientists in different locations and found to be true. Without repeated testing that give constant results, a scientific discovery can not be accepted by scientists.

plasma - state of matter made up of electrically charged particles