What type of port is used for Thunderbolt connections?

Thunderbolt connections utilize the USB Type-C port. This is because Thunderbolt 3 and Thunderbolt 4 technologies have standardized the use of the USB Type-C form factor, allowing for high-speed data transfer, video output, and power delivery through a single port. The versatility of USB Type-C supports various protocols, including Thunderbolt, which enables faster speeds and daisy-chaining of multiple devices. This alignment with USB standards is one of the reasons Thunderbolt has become widely adopted across various devices and platforms. The other options do not serve the same purpose or provide the same capabilities as USB Type-C for Thunderbolt technology.