Answer:
A. A historical account about the life of Beethoven.
Step-by-step explanation:
A research project is an act of trying to provide enough information by researching the topic. This process will provide the best and most truthful account of the research topic.
In Langston's research topic, he needs to finish his academic paper about Beethoven. By looking or referring to a text that contains the historical account of the famous composer and pianist, Langston will be able to provide the best and truthful account of Beethoven. A blog by a piano teacher, a movie review, or even a magazine article is just some third party details about the composer while a historical detail will contain the most truthful and detailed history of the composer.
Thus, the correct answer is option A.