Which of the following expansion slots is 64-bit?

The 64-bit expansion slot in the given choices is PCIe, which stands for Peripheral Component Interconnect Express. PCIe is a high-speed interface standard that connects internal components such as graphics cards, SSDs, and network cards to the motherboard. A notable feature of PCIe is that it supports various lane configurations, allowing for both 1-bit and wider data paths. The 64-bit capability refers to its ability to handle data in larger chunks at a time, significantly improving data transfer rates and overall performance compared to older standards.

For example, while other options such as PCI and ISA do exist as expansion standards, they do not support a 64-bit data path. Traditional PCI can transfer data in a maximum of 32 bits, while ISA is even older and supports only 16-bit data transfers. Hence, PCIe stands out as the modern standard designed to accommodate high-performance applications requiring 64-bit data transfer capabilities.