Which of the following is not a renewable source of energy?

Natural gas is a fossil fuel formed over ages, so it is not renewable.

Solar energy comes endlessly from the sun and is renewable.

Wind energy is renewable, driven by the atmosphere and ultimately the sun.

Ocean tidal energy renews with the gravitational pull of the moon and sun.

Fossil gas reserves deplete once used and cannot be quickly replaced.

Renewable sources refill on human timescales, unlike fossil fuels.