What is a long narrative poem that presents the adventures of heroic characters and important historical events?

The correct answer is defined as an epic, which is a lengthy narrative poem that explores the adventures and deeds of heroic figures and often encompasses significant historical events. Epics typically feature grand themes, larger-than-life characters, and the interplay between fate and human agency, usually set against a backdrop of major cultural or national significance.

For instance, works like "The Iliad" and "The Odyssey" by Homer are quintessential examples of epic poetry, showcasing the heroic journeys of figures like Achilles and Odysseus, while also reflecting the values and beliefs of ancient Greek society.

Other choices do not fit this definition: a sonnet is a 14-line poem typically focused on themes of love and nature; an ode is generally a lyrical poem that praises or glorifies a subject; and a ballad often tells a story in a more simplistic form, focusing on a singular event or a narrative in a musical, rhythmic style.