The phrase 'En route' means-

The correct answer is- ক) on the way.

En route:
- Bangla meaning: পথে; পথিমধ্যে।
- English meaning: on or along the way.

Example sentence:
1. They have arrived in London en route to the United States
2. We stopped at Paris en route from Rome to London.

Source:
1. Merriam-Webster dictionary.
2. Accessible Dictionary.
3. Cambridge Dictionary.