Compare and contrast the layers in your model, including the significance of the colors.

The right choice is  c. Water molecules have a weakly positive hydrogen end.

Explanation:

The unequal sharing of electrons in water molecule gives a slight negative charge near its oxygen atom ( see image below) and a slight positive charge near its hydrogen atoms. A neutral molecule that has a partial positive charge at one end and a partial negative charge at the other, it is a polar molecule.

so

a. Water molecules have a nonpolar bond.

It is wrong choice because water has polar bond .

b. Water molecules have a weakly positive oxygen end.  

Also, a wrong choice due to water molecule gives a slight negative charge near its oxygen atom.

c. Water molecules have a weakly positive hydrogen end.  

This is the right choice.

d. Water molecules have two oxygen and two hydrogen atoms

It is wrong choice because water has one oxygen and two hydrogen atoms

So, the right choice is

c. Water molecules have a weakly positive hydrogen end.