Explanation:

- Zeeman effect (Option 2)

- Correct. This effect is the splitting of a spectral line into multiple components in the presence of a magnetic field.

- It provides insights into the magnetic properties of atoms.

- *Askaryan effect* (Option 1)

- It refers to the phenomenon where a particle traveling faster than the speed of light in a dielectric medium produces a radio signal.

- Bezold effect (Option 3)

- A perceptual effect where the color of a pattern appears different due to the influence of adjacent colors.

- Domino effect (Option 4)

- A cumulative effect where a change or event causes a chain reaction.