After reading the passage, choose the best answer to each questions. (Question - 27 - 30)

Of Homer's two epic poems, the Odyssey has always been more popular than the Iliad, perhaps because it includes more features of mythology that are accessible to readers. Its subject (to use Maynard Mack's categories) is "life-as-spectacle," for readers, diverted by its various incidents, observe its hero Odysseus primarily from without; the tragic Iliad, however, presents "life-experience": readers are asked to identify with the mind of Achilles, whose motivations render him a not particularly likable hero. In addition, the Iliad, more than the Odyssey, suggests the complexity of the gods' involvement in human actions, and to the extent that modern readers find this complexity a needless complication, the Iliad is less satisfying than the Odyssey, with its simpler scheme of divine justice. Finally, since the Iliad presents a historically verifiable action, Troy's siege, the poem raises historical questions that are absent from the Odyssey's blithely imaginative world.

27. The author uses Mack's "categories" most probably in order to