One way to vary the syntax of the text is to combine sentences since, in this way, your structures will be longer and more complex to follow. This could be done by means of links such as: however, in addition, therefore, etc. When using these words, you create semantic relations between the syntactic structures and make the reading process more difficult because, as I've I said, sentences become longer and therefore the reader has to keep more information in mind to follow the train of thought.
You could also vary the syntax by adding phrases or clauses. This option is similar to the previous one since it also refers to the complexity of the syntactic structures of the text.
Answer:
I'm not quite sure if it's a or d most likely it's a according to me if I'm wrong please tell me right away I would really like to help you good day.
I believe there is a mistake in your choices, because I don't see the correct choice here. The correct answer should be ABAB ABCB.
This is because in the first stanza, the first line A (son) rhymes with the third line A (shun), and the second line B (catch) rhymes with the fourth line B (Bandersnatch) - which makes the first stanza ABAB.
In the second stanza, the first line A doesn't rhyme with anything (hand), the second line B (sought) rhymes with the fourth line B (thought), and the third line C doesn't rhyme with anything - which makes the second stanza ABCB.