The correct answer is: After 20 minutes.
A goods train shall be treated as overdue train after 20 minutes of its scheduled time of arrival. This is because the Indian Railways has a policy of treating any train that is delayed by more than 20 minutes as an overdue train. This policy is in place to ensure that passengers are not inconvenienced by delays and that they are able to make alternative arrangements if necessary.
The other options are incorrect because they are not the standard time that a goods train is treated as overdue. Option A is incorrect because a goods train is not treated as overdue after 10 minutes. Option B is incorrect because a goods train is not treated as overdue after 15 minutes. Option C is incorrect because a goods train is not treated as overdue after 25 minutes.
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