Which statement best defines Semi-Nested PCR?

Semi-Nested PCR is characterized by the inclusion of two primers from the initial amplification round, where one of them is used in a second amplification round along with a new inner primer. This technique allows for increased specificity and sensitivity in the amplification of a target DNA sequence. By utilizing one of the original primers and adding a new inner primer, the semi-nested approach also helps in minimizing the potential for non-specific amplification that could occur if only one primer were used.

This strategy is particularly valuable for applications such as detecting low-abundance targets or when working with complex templates, as it can enhance the yield of the desired amplicon while reducing background noise. Thus, the assertion that semi-nested PCR includes two identical primers from the first round effectively encapsulates the essence of the technique.