Q: Fact 1: If a neutral atom loses an electron then an atom with a negative charge will be formed. Fact 2: Ice crystals that are formed have a negative charge. Given the two facts above, ice crystals are formed when a neutral atom does what?

Select from:
[1]. adding heat;
[2]. vaporization;
[3]. flow of electrons;
[4]. loses an electron;
[5]. It remains dormant;
[6]. It gets heated up;
[7]. heating liquids;
[8]. evaporation;
The answer is:
[4].