Answer: D. Political Speech
Explanation: The answer is most likely D. A report is "a spoken or written account of something that one has observed, heard, done, or investigated," so it is based on fact, not opinion. Reference materials are just the pieces of information a speaker uses to create their speech, so is not an expression of their own opinion. A review is "an overview of the previously published works on a specific topic," so it is literally just reviewing a piece of work and analyzing its strengths and weaknesses.
A political speech is a "commentary on matters of public concern," so it would be expressing the speaker's views on certain issues, making the correct answer D.
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