Final answer:
The opening of Act II of Dido and Aeneas begins with a sprightly tune in the style of a dance.
Step-by-step explanation:
The opening of Act II of Dido and Aeneas begins with a sprightly tune in the style of a dance. This can be seen in the lively rhythm, energetic melody, and use of instruments typically associated with dance music. The music sets a joyful and celebratory mood, enhancing the overall theatrical experience and engaging the audience.