What is the term for the virtuosic, improvisatory passage played by the soloist in a Classical concerto?

Which record company launched the careers of Jerry Lee Lewis and Elvis Presley?

a. Sun b. RCA Victor c. Stax d. Atlantic

The poetic form using sets of three lines with the rhyme scheme aba, bcb, cdc, etc. is called __________

A) ?model form B) ?frame C) ?terza rima D) ?iambic pentameter