"mp" in music stands for "mezzo piano." Mezzo means medium and piano means soft, so therefore, the musician should play at a slightly reduced volume.
The correct option is B.
The source of information, that would offer the most reliable fact-based information about the author is a book, that is written by the author himself. This type of source is called primary source. Information obtained from Wikipedia, movie and books published by other authors can only offer secondary information, which are not as reliable as information from primary source.
Yea the answer above is right