What standard for wireless communications is used by the four major U.S. wireless network operators to expand their 4G networks?

The standard for wireless communications that the four major U.S. wireless network operators utilize to expand their 4G networks is Long Term Evolution (LTE). LTE represents a significant advancement in mobile technology, enabling faster data transmission rates and improved efficiency compared to previous generations. It supports various network configurations and enhances user experience by allowing seamless handling of voice and data services.

LTE is specifically designed to increase the capacity and speed of mobile networks, making it the backbone of 4G communications. This standard allows for better integration of mobile and internet services, which leads to improved performance for activities like streaming video or using data-heavy applications.

The other options refer to different types of technology that are not suited for the specific purpose of expanding wireless network infrastructure in the context of mobile telecommunications. Transmission Control Protocol is a foundational internet protocol for data transmission but doesn't directly relate to 4G network expansion. Bluetooth is a short-range wireless technology primarily used for connecting devices over short distances rather than cellular communications. Hypertext Transport Protocol is a protocol used for transmitting web pages over the internet, which is not applicable to cellular network standards.