Which of the following is the smaller version of DisplayPort?

The smaller version of DisplayPort is indeed Mini DisplayPort (often abbreviated as MiniDP or mDP). Mini DisplayPort is designed to carry the same high-quality video and audio signals as standard DisplayPort, but in a more compact form factor. This makes it particularly valuable in devices where space is limited, such as laptops and ultrabooks.

Mini DisplayPort was introduced by Apple, and it has become a standard in many devices, allowing users to connect to a variety of displays. It maintains compatibility with standard DisplayPort while providing a smaller connection option, making it easier to integrate into slim designs.

Other options do not refer to a smaller version of DisplayPort. HDMI is a different standard for audio and video transfer, focused on consumer electronics. USB-C is a versatile connector that can carry various types of data and power, but it is not a variant of DisplayPort. Thunderbolt, while it can also use the same physical connector as Mini DisplayPort, is a high-speed interface that can support multiple protocols, including DisplayPort, but it is not specifically a smaller version of it.