This group consists of non-renewable organic resources

The correct option is "natural gas, oil and coal".

To understand why this is the correct group, let's break down the definitions of the terms mentioned in the question:
1. Organic resources: These are resources derived from organic matter (decayed remains of plants and animals that lived millions of years ago).
2. Non-renewable resources: These are resources that exist in finite quantities and cannot be replenished or regenerated by natural means at a pace fast enough to keep up with consumption. Once used up, they are gone for all practical purposes because their formation takes millions of years.

Let's evaluate the substances listed in the correct option:
- Coal: Formed from fossilized plant remains under high pressure and temperature over geological timescales. It is organic and non-renewable.
- Oil (Petroleum): Formed from the remains of ancient marine organisms. It is organic and non-renewable.
- Natural gas: Often found alongside oil deposits, created from the decomposition of ancient organic matter. It is organic and non-renewable.

Therefore, natural gas, oil, and coal represent a group consisting entirely of non-renewable organic resources.