Practice question

Correct option is D, Purkinje fibers. In Cardiovascular System: Heart, the accurate description is Purkinje fibers, and that is what you should commit to memory. Keep the definition tight and the role clear — Purkinje fibers is the option that correctly names the structure, process, or principle asked for in Cardiovascular System: Heart. Then Purkinje fibers is the answer you can defend. Check yourself by covering the options and writing the answer first, then matching the letter — that builds confidence. If the wording feels dense, translate it into everyday language first, then map that plain sentence back onto Purkinje fibers. Remember that physiology questions reward precise language: name the process, the location, and the outcome, then match that to the option text.