Explanation:

DNA barcoding is primarily used for species identification. It involves the sequencing of a specific region of DNA in a sample and comparing it to a database to identify the species. This method is particularly useful for distinguishing among species that look alike, and it can be used to identify undesirable animal or plant materials in processed foods.

However, DNA barcoding is not used to assess the age of a plant or animal.

So, the correct answer is: Only Two