Irreversible Process

Assertion : A quasi static isothermal expansion of an ideal gas in a cylinder fitted with a frictionless movable pistonis a irreversible process. Reason : A process is irreversible only if system remains in equilibrium with the surroundings at every stage.

What will be the change in entropy in an irreversible cyclic process ?

Can an isothermal process be irreversible ?

Why are spontaneous/natural processes irreversible?

Which of the following processes are irreversible?