Scientists claim that climate change is happening because Earth is warming. They also claim that humans have helped cause the warming by adding greenhouse gases to the atmosphere. Other people claim that Earth is not experiencing climate change because some winter days are still very cold. Use evidence to evaluate each claim about climate change.

We know it’s C because of what it says in the text

Enzyme make a hormone as a catalyst

You would be correct, boiling water does disinfect contamination.    the property of disinfecting means to kill  germs, bacteria and other pathogens or contamination  that might cause an infection or cause a person to become sickly. a couple methods of disinfecting are using soap, other cleaning supplies or by simply "boiling" the contaminate.  the reason why boiling water disinfects certain attributes is because some cells cannot survive the heat and pressure.