The injected LacZ$-$expressing cells from question #$10$ are monitored over time before and after treating the mice using your combination treatment from question #$8.$ Which of the following observations is consistent with the behavior of a stem cell population? $(2$pt$)$

Group of answer choices

A$)$ LacZ$-$positive cells expand within the tumor. Treatment kills off the tumor cells but not the LacZ$-$expressing cells. The tumor does not grow back.

B$)$ LacZ$-$positive cells expand within the tumor. Treatment kills off the tumor cells but not the LacZ$-$expressing cells. The tumor regrows with LacZ$-$positive cells.

C$)$ All of the LacZ$-$positive cells differentiate into pancreatic cells and begin secreting insulin. Treatment kills off the tumor cells but not the LacZ$-$expressing cells. The tumor does not grow back.

D$)$ All of the LacZ$-$positive cells differentiate into pancreatic cells and begin secreting insulin. Treatment kills off the tumor cells and the LacZ$-$expressing cells.