Final answer:
Alpha particles, which are positively charged, are repelled by the positively charged gold nuclei due to the repulsive electrostatic force, causing some alpha particles to deflect during the gold foil experiment.
Step-by-step explanation:
In the context of the classic gold foil experiment carried out by Rutherford at the beginning of the 20th century, the particles in question are alpha particles, which are known to be positively charged. When these alpha particles were accelerated towards the gold foil, which consists of atoms with positively charged nuclei, the Coulomb force came into play. Specifically, the repulsive electrostatic force between the similarly charged alpha particles and the gold nuclei caused some particles to be deflected.
Given that like charges repel each other, alpha particles will be repelled from the positively charged gold nuclei. The particles in the beam formed by alpha particles will be scattered by the repulsive electrostatic force from the positive nuclei of the gold atoms, as mentioned in option c. This behavior led to the conclusion that gold atoms, and by extension all atoms, have a compact, positively charged nucleus that contains most of the atom's mass.