The director's talent for successful improvisation is illustrated by

1. the use of black spirituals in an opera
2. the composer's brief acquaintance with Harriet Tubman's star
3. the way the other singers support the opera's star
4. last m-minute use of a dancer to portray Harriet's actions
5. the use of a harp as banjo

my best answer is 4 ?!?!

Yes, 4 is correct.

To determine which answer option best illustrates the director's talent for successful improvisation, we need to carefully analyze each option and see which one aligns with the concept of improvisation.

1. The use of black spirituals in an opera: This option may show creativity or innovation in integrating different musical styles, but it doesn't necessarily highlight improvisation.

2. The composer's brief acquaintance with Harriet Tubman's star: This option talks about the composer's connection to Harriet Tubman's star, but it doesn't directly relate to the director's talent for improvisation.

3. The way the other singers support the opera's star: While this option shows collaboration and support among the singers, it doesn't specifically depict improvisation.

4. Last-minute use of a dancer to portray Harriet's actions: This option suggests a situation where the director spontaneously incorporates a dancer to represent Harriet Tubman's actions. This demonstrates the director's ability to make quick decisions and adapt to unforeseen circumstances, indicating improvisation.

5. The use of a harp as a banjo: While the use of unusual instruments can be creative, it doesn't necessarily identify the director's talent for improvisation.

Based on this analysis, it appears that your best answer is indeed option 4 - the last-minute use of a dancer to portray Harriet's actions.