The correct answer is: C. 10 minutes.
A goods train is considered delayed if it does not arrive within 10 minutes of its scheduled arrival time. This is because goods trains are often used to transport time-sensitive goods, such as fresh produce or perishable goods. If a goods train is delayed, it can cause significant disruption to businesses and consumers.
The other options are incorrect because they are not the standard time limit for considering a goods train to be delayed. Option A, 3 minutes, is too short a time limit. Option B, 4 minutes, is also too short a time limit. Option D, 20 minutes, is too long a time limit.
In conclusion, the correct answer to the question “If the goods train is not arrived __ minutes beyond its normal running time, it is treated as delayed train” is C. 10 minutes.