Answer:
C. melting
option C is correct answer.
We have to wonder what substance you're working with. Under normal, human environmental conditions, there are almost no substances that freeze and boil at the same temperature.
However, EVERY substance has SOME temperature, at some pressure, at which it "sublimes" ... passing directly from solid to gas, or from gas to solid, without existing in liquid form in between. Even water does that, if the conditions are right.
The correct answer is
<span> (3) 3.2 × 10^−19 C
In fact, electric charge is quantized: the elementary charge is the charge of the electron, </span>

, and every particle can only have an electric charge which is an integer multiple of this value. Of the options listed above, only option (3) is an integer multiple of the elementary charge: in fact, it corresponds to 2 times the electron charge: