Oxygen is absorbed from the air. Heat is radiating in the liquid. The boiling point has been reached. Molecular stability in the liquid is increasing.
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: What has occurred when bubbles form in a liquid that is being heated?
Possibilities:
- Oxygen is absorbed from the air.
- Heat is radiating in the liquid.
- The boiling point has been reached.
- Molecular stability in the liquid is increasing.

The boiling point has been reached.