The process which is best described by "A" in this Venn diagram is: C. fusion of atoms.
Nuclear fusion can be defined as a type of nuclear reaction that involves joining or combining two (2) smaller nuclei of atoms, so as to form a single heavier nucleus accompanied with the release of energy.
Based on the Venn diagram in the image attached below, we can logically deduce that the process which is best described by "A" is fusion of atoms.
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