Was one of the most lucrative parts of the music business at the end of the nineteenth century. a. providing music lessons b. giving concerts c. writing sheet music d. selling instruments

Hi there!

The answer is A. Providing music lessons. 

Many famous composers took to giving music lessons to make money. Providing music lessons was one of the most lucrative parts of the music business at the end of the nineteenth century. 

Hope this helps!

What painting? can you post a picture

Answer:   a thesis statement is the subject of the whole paragraph and is a generality.
a thesis statement clears everything up. its located at the end of an introductory  paragraph  that  summarizes  the point of the essay in all just one or  two  sentences.