What is the structure of a Petrarchan Sonnet?

The structure of a Petrarchan sonnet consists of an octave followed by a sestet. The octave typically presents a problem, situation, or emotional state in eight lines, often following an ABBAABBA rhyme scheme. The sestet, which consists of six lines, usually offers a resolution or response to the situation introduced in the octave and can vary in rhyme scheme, such as CDCDCD or CDECDE. This division allows for a clear shift in theme or tone, making it a distinctive and effective form in poetry, especially in expressing complex feelings or ideas.

In contrast, other forms mentioned do not adhere to this particular structure; three quatrains and a couplet align more with the Shakespearean sonnet, while five unrhymed lines do not fit any sonnet form. Two rhymed lines could refer to a couplet but lacks the deeper complexity found in a Petrarchan sonnet. Thus, option C accurately captures the essence of a Petrarchan sonnet's structure.