基于"方言与普通话共存"话题，演讲者的论证连贯性如何？
- 以家庭用方言与课堂用普通话为例，说明场合决定语言选择 (correct answer)
- 只说方言很有趣，缺少与沟通需求相关的具体说明
- 把重点转到数学竞赛，例子与语言共存无关联
- 先说应保护方言又说必须全部取消，立场矛盾不一致
Explanation: This question tests AP Chinese Language and Culture skills, specifically the ability to explain ideas and opinions with examples in spoken presentations. Effective communication in presentations involves clearly articulating ideas and supporting them with relevant, coherent examples. In this scenario, the speaker discusses the coexistence of dialects and Mandarin, using family dialect use and classroom Mandarin examples to show that context determines language choice. Choice A is correct because it accurately reflects how the speaker's examples are relevant and enhance understanding of the topic. Choice B is incorrect because it misinterprets the examples used by the speaker, focusing on irrelevant details. To help students: Encourage the practice of structuring presentations with clear examples, and reinforce the importance of coherence. Use exercises that focus on comparing effective vs. ineffective examples. Watch for: Students using irrelevant or unsupported examples.