Question

mitosis is important because it allows
new cells to replace old damaged cells.
new cells to repair old damaged cells.
old cells to self - repair when they become damaged.
existing cells to take over the function of damaged cells.

Explanation:

Mitosis is a type of cell division. During mitosis, one cell divides to form two identical daughter cells. In the body, when cells are old or damaged (for example, skin cells getting worn out), mitosis occurs. The new cells produced by mitosis have the same genetic information as the original cells. These new cells can then take the place of the old or damaged cells. For instance, in the lining of the gut, mitosis constantly produces new cells to replace those that are shed or damaged. It's not about repairing the old cell itself (as in option 2 and 3 - the old cell doesn't self - repair in the sense of mitosis; instead, it's replaced). Also, it's not about existing cells taking over functions (option 4 - it's about generating new, identical cells to replace).

Answer:

new cells to replace old damaged cells.