Step 1: Recall the facts:
Think of the kriya where the belly is pulled in again and again with short sharp exhalations. That practice is known as the skull-shining breath.
Step 2: Match the facts with the options:
Option (1): Tratak is an eye exercise where we stare at a point. No breathing drill is involved, so it does not fit.
Option (2): Neti is nose cleaning with water. It does not use the diaphragm forcefully, so it does not fit.
Option (3): Kapalbhati has active, sharp exhalations driven by the diaphragm and abdomen, with passive inhalation. It fits exactly.
Option (4): Dhauti cleans the digestive tract. It is not a breathing practice, so it does not fit.
Step 3: Decide:
Only Kapalbhati combines fast, forceful breathing with diaphragm action, so it is the answer.
Final Answer:
Option (3) is correct. \[\boxed{\text{Kapalbhati}}\]