Which term describes an enzyme?

What defines an enzyme?

The ever famous description :

All enzymes are proteins but not all proteins are enzymes.

Oh I remember that well.

So the other descriptions of enzymes are :

Sensitive to Heat

Sensitive to pH

A catalyst

Specific substrates

the answer is c) abandoned properties that are contaminated with hazardous materials.

relative humidity, temperature and dew point -- are bound together in the mathematical relationship below. relative humidity changes when temperatures change. because warm air can hold more water vapor than cool air, relative humidity falls when the temperature rises if no moisture is added to the air. so i would say a