The diagrams below represent the four states of matter. A number of blue balls are loosely packed in a container. A number of yellow balls are randomly distributed in a container.
Diagram 1 Diagram 2

A number of red balls are tightly and neatly packed in a container. A number of balls are positioned randomly in a container. Some are pink and labeled with a plus sign and some are blue and labeled with a minus sign.
Diagram 3 Diagram 4

Which diagram represents a gas that has been ionized?
diagram 1
diagram 2
diagram 3

Diagram 4

Explanation: Diagram 1 represents a state in which particles are closely packed , thus cannot be a representation of gas.

Diagram 2 represents  a state in which particles are loosely packed , thus can be a representation of gas.

Diagram 3 represents  a state in which particles are closely packed , thus can be a representation of a solid.

Diagram 4 represents  a state in which particles are loosely packed , thus can be a representation of gas. It also represents the particles in ionized form. Particles are existing as ions bearing positive and negative charges.

Explanation:

the answer is option a.