This question is testing COMPARISONS and MODIFIERS.

A. The work of Byron and Shelley, like other poets of their era, explored themes of love and beauty, which gave rise to the school of poetry known as Romanticism.
- "work" can't be like "other poets." We'd have to say "like that of other poets"
- "which" is modifying "themes of love and beauty." It seems unlikely that themes gave rise to a school of poetry. We shouldn't use the noun modifier "which" here; we should use an adverbial modifier.

B. Byron and Shelley, like other poets of their era, explored themes of love and beauty in their work, giving rise to the school of poetry known as Romanticism.
- correct comparison of poets to poets
- correct adverbial modifier

C. Like other poets of their era, Byron and Shelley's work explored themes of love and beauty, giving rise to the school of poetry known as Romanticism.
- incorrectly comparing "like other poets" to "work"

D. Love and beauty are themes explored by the work of Byron and Shelley, like they were by other poets of the era, and they gave rise to the school of poetry known as Romanticism.
- "like they were" is not idiomatic. If comparing clauses, we should say "as they were."
- "they gave rise" = love and beauty gave rise. Illogical.

E. The school of poetry known as Romanticism rose from the works of Byron and Shelley, which was like that of other poets of the era in exploring themes of love and beauty.
- "gave rise" is the correct idiom when one thing led to / created another. "Rose from" is not idiomatic.
- "which was" is incorrectly referring to "works" plural
- the modifier beginning with "which" contains so many prepositional phrases that it's hard to untangle the meaning

The correct answer is [spoiler]B.
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