Water molecules exhibit a property by virtue of which they can stick to each other. what is this property referred to as?

The water molecule has the ability to form hydrogen bonds, between atoms of oxygen and hydrogen of different molecules (they can also be formed between atoms of hydrogen, phosphorus, and nitrogen, but in the case of water we refer only to hydrogen and oxygen). When this phenomenon occurs between molecules of the same species (one molecule of H2O with another molecule of H2O), it is called cohesion, which is the attraction that molecules have for others of the same type. In the case of water, cohesion occurs thanks to hydrogen bonds, and this union is very strong and difficult to break.

of those who start drinking before they're 15 will develop alcohol dependence

the answer will be a) proteins i believe