A population of "X" cells divide, becoming a population of "Y" and "Z" cells.  The "Y" and "Z" cells are distinctly different.  "Z" cells then secrete a protein that changes some nearby "Y" cells into "A" cells.  Which of the following is correct?Group of answer choicesThe population of "X" cells underwent symmetric division, and the population of "Y" cells underwent asymmetric cell division.Both the population "X" and "Y" cells underwent asymmetric division.The population of "X" cells underwent asymmetric division, and "Z" cells produced a morphogen."X" cells and "Z" cells must produce morphogens.

The correct answer is: The population of "X" cells underwent asymmetric division, and "Z" cells produced a morphogen.

Here's why:

1. Asymmetric division: This is when a cell divides into two daughter cells that are not identical - they have different cell fates. In this case, the "X" cell divides into two different types of cells - "Y" and "Z". This is an example of asymmetric division.

2. Morphogens: These are substances that determine the fate of cells and their spatial positioning within the organism based on their concentration. In this case, the "Z" cells secrete a protein that changes the "Y" cells into "A" cells. This protein acts as a morphogen.

Therefore, the "X" cells underwent asymmetric division (since they divided into two different types of cells), and the "Z" cells produced a morphogen (the protein that changes "Y" cells into "A" cells).