Question

why does a cell need to copy its dna?

to store extra copies of dna in your liver
to ensure that each new cell gets a copy of dna

Explanation:

When a cell divides (as shown in the diagram), each new daughter cell needs to have a complete set of genetic information. DNA contains the instructions for the cell's functions. If the DNA isn't copied, new cells would lack the necessary genetic material. Storing extra copies in the liver is not the main reason for DNA copying in general cell division. The key is to provide each new cell with its own DNA copy for proper functioning and development.

Answer:

to ensure that each new cell gets a copy of DNA