What is quantum advantage?

What does quantum advantage generally mean?

A

A quantum device solves a task while using fewer physical qubits than a classical machine uses bits

B

A quantum device solves a meaningful task better than the best known classical approach under defined conditions

C

A quantum device solves every computational task faster than any classical machine, whatever the problem is

D

A quantum device solves a task that no classical machine could ever solve, even with unlimited time