Answer:
All sentences apply to the question.
Explanation:
To study a sonnet means to learn many aspects related to this specific expression of literary creation, such as its structure, the common subjects materialized throughout the years, sonnet's rhyme squemes patterns, how to analyse and understand a sonnet and its possible meanings, and more. However, the last sentence only applies because it is an example of how to analyse sonnets, such as by the use of comparative literature analysis in which it is compared both Shakespeare's sonnets and Petrarch's.
