Step 1: Define Bandwidth.
Bandwidth is the range between the maximum and minimum frequencies a channel can utilize for data transmission, signifying its data-carrying capacity.
Step 2: Analyze Options.
- Option 1: Correct → This accurately defines bandwidth as the available frequency range.
- Option 2: Incorrect → This describes a transmission route, not bandwidth.
- Option 3: Incorrect → Internet regulations are protocols, not bandwidth.
- Option 4: Incorrect → This refers to the data itself, not channel capacity.
Final Answer: \[\boxed{\text{Bandwidth = Range of frequencies available for transmission.}}\]