Generally short circuit fault in a transformer is protected by:

Correct option is D

 Merz-Price protection is a differential protection scheme commonly used for transformers.
 It is designed to detect internal faults such as short circuits by comparing the current entering and leaving the transformer.
 If there is a significant difference between the two currents, it indicates a fault, and the relay operates to isolate the transformer from the system.
 This method is effective in protecting transformers from short circuit faults.