How does DNA replication give rise to variations?

How does DNA replication give rise to variations?

Answer:

• If the daughter cells produced are completely identical to the parent or not depends on how accurately the DNA copy is made .
• Since no biochemical reaction is completely reliable, some errors are expected to occur in the DNA copying which results in variation . 
• Because of these variations, the daughter cells are similar but not completely identical to the parent .
• If these variations are very drastic, the DNA may not be able to work and the cell dies.
• These discrepancies form the basis of evolution .