Step 1: Several named techniques exist for tubal ligation, each defined by how the fallopian tube is handled.
Step 2: The Kroener method removes the fimbrial end of the tube, so it is the technique that corresponds to fimbriectomy, making option D correct.
Step 3: The other methods differ: the Uchida technique injects saline subserosally to raise a bleb, the Irving method buries the cut tubal ends, and the Madlener technique crushes a loop of tube with forceps. None of these is a fimbriectomy.