The correct answer is: d) Not currently planned.
Hyperloop is a proposed mode of transportation that uses a sealed tube to transport people or objects at high speeds using magnetic levitation. The technology is still in the development stage, and there are no plans to build a hyperloop system in India at this time.
The other options are incorrect because they are all cities in India that are currently connected by rail or air. Chennai and Bengaluru are the two largest cities in the state of Tamil Nadu, and they are connected by a high-speed rail line. Madurai and Coimbatore are two other major cities in Tamil Nadu, and they are connected by a regular rail line.
It is possible that hyperloop technology could be used to connect cities in India in the future, but there are no concrete plans to do so at this time.