Final answer:
WiFi, cell tower broadband, and a USB cable to a router are used for mobile Internet access.
Step-by-step explanation:
The three options that are used for mobile Internet access are: WiFi, cell tower broadband, and a USB cable to a router.
WiFi allows devices to connect to the Internet wirelessly by establishing a connection to a nearby router. Cell tower broadband refers to the use of cellular network connections provided by mobile service providers. A USB cable can be used to connect a device to a router, providing Internet access.
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