The correct answer is: c) Upgrading the existing highway.
The ongoing project to improve connectivity between Imphal and Moreh town on the Myanmar border focuses on upgrading the existing highway. The project is being implemented by the National Highways and Infrastructure Development Corporation Limited (NHIDCL) and is expected to be completed by 2023. The project will involve widening the highway from two lanes to four lanes, improving the surface of the road, and constructing new bridges and culverts. The upgraded highway will improve connectivity between Imphal and Moreh, which is a major trading point between India and Myanmar. It will also boost economic activity in the region and facilitate trade and commerce.
Option a) is incorrect because the project does not involve developing a high-speed rail line. Option b) is incorrect because the project does not involve developing a new expressway. Option d) is incorrect because the project does not involve developing a waterway system.