Gases are very easy to compress. The best explanation for this is that

gaseous molecules are far apart

Explanation:

One of the states in which matter exists is gas. Gases are made of up molecules that are far apart, travelling randomly and rapidly within the containing vessel.

Hence, they are easy to compress whereby they occupy limited space as the gaseous molecules are closely packed in vessels like cylinders and transported to places where they may be needed.

The individual molecules of gases are quite far apart.

Explanation: Gases are compressible since their molecules are far apart from each other and have so much space to move through. Due to this, gas molecules can occupy those gaps during compression having their molecules close to each other.

the answer is symmetrical : )