Concept:An ode is a lyric poem written to praise or celebrate a person, object, or event.
Explanation:A sonnet is a fourteen-line poem with a fixed rhyme scheme.
A dirge is a mournful poem or song composed for someone who has died.
A ballad is a narrative poem that often tells a story of adventure or love.
An ode, however, is specifically written to honour or celebrate its subject.
Therefore, the correct choice is the poem form that matches this purpose.
Answer:C. an ode