Assertion (A) Hydrocarbons are very good fuels. Reason (R) The main sources of hydrocarbons are natural gas, petroleum and coal. A. Both A and R are true and R is the correct explanation of A B. Both A and R are true, but R is not the correct explanation of A C. A is true, but R is false D. A is false, but R is true

The correct answer is: Both A and R are true, but R is not the correct explanation of A.

Hydrocarbons are very good fuels because they are highly flammable and release a lot of energy when they burn. However, the main sources of hydrocarbons are not the only sources of good fuels. For example, hydrogen is also a very good fuel, but it is not a hydrocarbon.

The reason (R) that the main sources of hydrocarbons are natural gas, petroleum and coal does not explain why hydrocarbons are very good fuels. The reason that hydrocarbons are very good fuels is because they are highly flammable and release a lot of energy when they burn.

Here are some additional details about each option:

• Option A: Both A and R are true and R is the correct explanation of A. This option is incorrect because the reason (R) that the main sources of hydrocarbons are natural gas, petroleum and coal does not explain why hydrocarbons are very good fuels.
• Option B: Both A and R are true, but R is not the correct explanation of A. This option is correct because both A and R are true, but the reason (R) that the main sources of hydrocarbons are natural gas, petroleum and coal does not explain why hydrocarbons are very good fuels.
• Option C: A is true, but R is false. This option is incorrect because R is true.
• Option D: A is false, but R is true. This option is incorrect because A is true.