Step 1: Place the waves on the frequency line:
Going from low to high frequency the wireless waves come in this order: radio waves, then microwaves, then infrared. So each range should start where the one before it ends.
Step 2: Use the known boundaries:
Infrared starts at 300 GHz and goes up to 400 THz, and microwaves go from 1 GHz to 300 GHz. So the radio waves must end at 1 GHz, where microwaves begin. Their lower end is 3 KHz.
Step 3: Compare with the options:
Option 3 is the infrared range, so it is out. Option 2 is a slice inside the microwave range, so it is out. Option 1 stretches up to 300 GHz, which swallows the whole microwave range, so it is out.
Step 4: Pick the match:
Option 4 starts at 3 KHz and stops at 1 GHz, exactly as the boundary check says.
Final Answer:
Radio waves cover 3 KHz to 1 GHz.
\[ \boxed{\text{3 KHz to 1 GHz}} \]