Pure substances can be classified into element and compound. Choose the CORRECT pair(s).
I Diamond - element
II Salt - compound
III Sugar solution - element

I and Il only
I only
II and III only
III and III

a patient chooses to not take a beneficial medical treatment.

explanation:

the answer is c

tell me if wrong

ca has a crystalline lattice with positive ions (since it is a metal, metals are positively charged) and electrons flow freely in its structure since the ca atoms have a large nuclear radius so the electrons are not tightly held, therefore the electrons can flow freely since they are not being highly attracted by the nucleus. moreover, one of the properties of metals are that they are conductors of electricity, thus proving ca is the element.