You answered incorrectly.
The correct answer is (e), all the above. Because of the extent of myocardium at jeopardy and the complexity of the Left Main PCI potentially causing prolonged ischemia, hemodynamic support (a) is important for certain cases to provide safety as well as time to achieve quality PCI results regardless of baseline LV function. (b) is correct because it reflects the fact that significant disease is rarely isolated to the Left Main itself and thus involves associated vessels including the LAD, Circumflex as well as potentially a Ramus artery. Managing such bifurcation lesions is an important component of success. Intravascular imaging (c) is particularly important in Left main and associated bifurcation lesions to assess vessel size and vessel coverage to choose appropriately sized stents and likewise for the assessing quality of stent expansion post implantation. Lastly, atherectomy (d) is critical to manage vessel calcium ensuring easier stent delivery as well as improved stent expansion.