Final answer:
The current mobile service using LTE technology is 4G or 'fourth generation.' This technology is known for providing faster data speeds than 3G and is a step before the newer 5G technology.
Step-by-step explanation:
The current rollout of mobile service that uses LTE technology is B) 4G. LTE stands for Long-Term Evolution and is considered a 'fourth-generation' technology. The progression of mobile networks started with 1G, then moved to 2G, 3G, and most currently, 4G LTE. It is the 4G LTE that provides users with faster data speeds compared to its 3G predecessor. While 5G is also being rolled out in some areas, it is not based on LTE technology but rather a new set of standards which is even faster and more efficient than 4G LTE.