The modern model of the atom shows that electrons are(1) orbiting the nucleus in fixed paths(2) found in regions called orbitals(3) combined with neutrons in the nucleus(4) located in a solid sphere covering the nucleus

The correct answer is 2. Electrons are found in regions called orbitals. These orbitals are neither fixed paths nor solids, but are better visualized as cloud-like space, making 1 and 4 incorrect. Additionally, 3 is incorrect because the orbitals are outside of the nucleus, while the protons and neutrons are inside the nucleus. Hope I helped! :) Cheers!

Alpha particles have positive charge, beta particles have negative charge, and answer 4 just doesn’t make sense. thus, you are left with only one possible answer.