what did thomsons model of the atom include that daltons model did not have?\n a nucleus\n energy levels\n…

Brief Explanations:

Dalton's model considered atoms as indivisible solid spheres. Thomson discovered electrons, showing atoms have smaller - sub - atomic particles. His plum - pudding model had electrons (smaller particles) embedded in a positive sphere. Nucleus was discovered later by Rutherford, energy levels and electron clouds are concepts from later atomic models.

Answer:

D. smaller particles