SAT English Practice Question

The writer uses the word "but" to introduce a contrast between the two parts of the sentence. In the first part, the writer describes the popularity of the new format. In the second part, the writer describes the difficulty of implementing the new format. What is the most likely reason why the writer uses the word "but"?

1. A.create a sense of surprise and excitement.
2. B.suggest that the writer is unsure about the topic.
3. C.highlight the complexity of the topic.
4. D.indicate the writer’s preference for one format over the other.