Oil is a renewable resource releases more toxins than coal must be mined from underground can easily be replenished

The correct answer for the blank is -

must be mined from underground.

Oil is considered as a fossil fuel as it is formed by the dead remains of plants and animals that lived on earth millions of years back.

It is a non renewable source of energy because it can not be replenished readily by natural means and to renew, it would again require millions of years.

Mining of oil is a process of extraction  of fossil fuels from underground, which is based on the digging of underground mining excavations.

Thus, oil must be mined from underground is the right answer.

b. lifting dumbbell weight at 20-degree angle from the body after a 45-degree angle