Final answer:
Beethoven's second period, known as his heroic period, is characterized by his compositions with heroic themes.
Step-by-step explanation:
Beethoven's second period is often referred to as his heroic period because most of his works from this period had heroic themes. In this period, Beethoven composed symphonies such as his Third Symphony, known as the Eroica Symphony, which was dedicated to Napoleon Bonaparte. He also composed other works with heroic elements, such as his Symphony No. 5 with its famous opening motif. These works showcase Beethoven's exploration of the heroic and dramatic in his music.