The first musical presentation that the public could buy tickets to was at the St. Cassiano Theater in Venice, which opened in 1637. This theater marked the beginning of public opera houses and ticket sales for performances. Other options listed were significant, but they did not precede this historic venue. ;
The St. Cassiano Theater in Venice was the first public opera house where tickets were sold, opening in 1637. Other venues listed did not precede this milestone in the accessibility of music performances. Therefore, the correct answer is D: The operas at the St. Cassiano Theater in Venice.
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