What can be said about atomic nuclei A with 96 protons and 148 neutrons, and B with 94 protons and 150 neutrons?

Atomic nuclei are defined by their number of protons and neutrons. The number of protons in an atomic nucleus determines the identity of the element, which is referred to as the atomic number. In this case, nucleus A has 96 protons, while nucleus B has 94 protons. Since these two nuclei have different numbers of protons, they correspond to different elements.

Nucleus A, with 96 protons, is the element Curium (Cm), whereas nucleus B, with 94 protons, is Plutonium (Pu). The difference in the number of neutrons does not change the identity of the element, though it can affect the stability of the isotopes formed by those elements.

Thus, the correct assessment is that A and B represent different elements, further indicated by their differing atomic numbers. As such, understanding the relationship between protons and element identity is essential in nuclear physics and helps to distinguish between isotopes of the same element, which would require identical proton counts. The other options misinterpret the atomic structure related to isotopes and elements.