The correct answer is option 'C', Bangladesh. The Bandhan Express and Maitree Express are train services that run between India and Bangladesh. These train services have been in the news as they play a significant role in strengthening the bilateral ties and promoting people-to-people connectivity between the two countries.

The Bandhan Express and Maitree Express are part of the efforts made by India and Bangladesh to enhance regional connectivity and facilitate easier travel for the people of both countries. These train services have been established to provide a convenient and comfortable mode of transportation for passengers traveling between India and Bangladesh.

Bandhan Express:
- Bandhan Express is an international passenger train service that operates between Kolkata in India and Khulna in Bangladesh.
- It was inaugurated on November 9, 2017, by Prime Minister Narendra Modi of India and Prime Minister Sheikh Hasina of Bangladesh.
- The train runs every Thursday from Kolkata and every Friday from Khulna.
- It covers a distance of approximately 172 kilometers and takes around four hours to complete the journey.
- Bandhan Express is an important symbol of the close ties and cooperation between India and Bangladesh.

Maitree Express:
- Maitree Express is another train service that connects Kolkata in India with Dhaka, the capital city of Bangladesh.
- It was inaugurated on April 14, 2008, by Prime Minister Sheikh Hasina and Prime Minister Manmohan Singh of India.
- The train runs six days a week, except for Sundays, from Kolkata to Dhaka and vice versa.
- Maitree Express covers a distance of approximately 375 kilometers and takes around 10-12 hours to complete the journey.
- This train service has been instrumental in promoting tourism, cultural exchange, and trade between India and Bangladesh.

These train services have not only facilitated easier travel for passengers but have also contributed to the economic development and growth of both countries. They have strengthened people-to-people contacts, fostered cultural exchanges, and promoted trade and tourism between India and Bangladesh. The Bandhan Express and Maitree Express have become important symbols of the friendly and cooperative relations between the two neighboring countries.