The numbers of nucleons required to generate complete shells in the nucleus are called: A. nuclear numbers
B. shell numbers
C. special numbers
D. magic numbers

The correct answer is option D, that is, magic numbers.

Explanation:

The magic number in nuclear physics refers to the number of nucleons, that is, either neutrons or protons, distinctly, such that their alignment results in the formation of complete shells within the nucleus of the atom. As a consequence, atomic nuclei comprising a magic number of neutrons or protons are much more stable in comparison to other nuclei.  

The seven most broadly known magic numbers are 2,8,20,28,50,85 and 126.  

idk what is it? is this a question that you know the answer or u dont