Which of the following is responsible to rule out the existence of definite paths or trajectories of electrons?

1. Pauli's exclusion principle

2. Heisenberg's uncertainty principle

3. Hund's rule of maximum multiplicity

4. Aufbau principle

Hint: Position of electron and momentum of electron cannot calculate simultaneously

Werner Heisenberg, a German physicist in 1927, stated uncertainty principle which states that it is impossible to determine simultaneously, the exact position and exact momentum of an electron.
Mathematically, x×ph4π
The important implications of the Heisenberg uncertainty principle is that it rules out existence of definite paths or trajectories of electrons and other similar particles.