The waves used in communication are generally called (A) \(\gamma\) rays (B) \(\alpha\) rays (C) microwaves (D) radiowaves

To determine which type of waves are used in communication, let's first understand what each option represents: (A) \(\gamma\) rays are a form of ionizing radiation, meaning they have the potential to damage human tissue and electronic components. They are not used in communication because of their destructive nature. (B) \(\alpha\) rays are particles (helium nuclei) that are also ionizing radiation. Due to the penetration capacity of \(\alpha\) rays, they are also not used in communication. (C) Microwaves are a form of non-ionizing radiation. They have a frequency range of 300 MHz to 300 GHz and are commonly used for communication because they can penetrate through obstacles and travel long distances. (D) Radiowaves have a lower frequency range than microwaves, which is 3 kHz to 300 GHz, and are a form of non-ionizing radiation. They are used for communication, especially in radio and television broadcasts, but not as commonly as microwaves for all types of communication systems.

Since we investigated all options, we can now identify the correct answer. In communication systems, microwaves are commonly used because of their ability to easily penetrate through obstacles and travel long distances. Therefore, the correct answer is: (C) microwaves