The correct answer is option 'C', which states that the train route distance from Kerala to Goa is 850 km. Let's explore why this is the correct answer.

1. Train Route:
- Kerala and Goa are two states located in southern India.
- Several train routes connect these two states, providing convenient transportation options for travelers.

2. Distance Calculation:
- The distance between Kerala and Goa can be calculated by measuring the straight-line distance or the actual distance covered by the train route.
- In this case, the question asks for the train route distance, which means we need to consider the actual distance covered by the train.

3. Actual Distance:
- The actual distance between Kerala and Goa depends on the specific train route chosen.
- However, based on commonly used train routes, the approximate distance between the two states is 850 km.
- This distance may vary slightly depending on the starting and ending points within Kerala and Goa.

4. Importance of the Correct Answer:
- Knowing the correct train route distance is essential for planning a journey.
- It helps travelers estimate the travel time, make necessary arrangements, and prepare accordingly.

In conclusion, the train route distance from Kerala to Goa is approximately 850 km. It is crucial to have accurate information about the distance to plan a comfortable and efficient journey.