**Core Concept:** DNA technology involves various techniques used to study, manipulate, or analyze the genetic material. Oligonucleotides are short segments of DNA or RNA with specific sequences. Single base pair substitution refers to a mutation where only one nucleotide is changed in the DNA sequence.

**Why the Correct Answer is Right:** The correct answer is Polymerase Chain Reaction (PCR). PCR is a molecular biology technique used to amplify specific regions of DNA. It involves the use of an enzyme called DNA polymerase, which synthesizes complementary DNA strands from a single DNA strand template. A single base pair substitution can introduce a mismatch, allowing the primers to bind specifically to the mutated region, enabling PCR to amplify that particular DNA segment.

**Why Each Wrong Option is Incorrect:**

A. Restriction Enzyme Digestion (RED) is a technique used to cut DNA at specific sites, based on known restriction sites. It does not involve single base pair substitution or amplification of specific DNA segments.

B. Southern Blotting is a technique used to detect and locate specific DNA fragments on a gel by hybridization. It does not involve amplification of DNA segments nor single base pair substitutions.

C. DNA Sequencing is a method used to determine the order of nucleotides in a DNA molecule. While it can detect single base pair substitutions, it does not involve amplification of specific DNA segments.

D. DNA Ligase is an enzyme involved in DNA repair, joining broken DNA strands. It does not involve amplification of specific DNA segments nor detect single base pair substitutions.

**Clinical Pearl:** Understanding the correct answer, PCR, and its applications is crucial in molecular biology research, genetic diagnosis, forensic science, and genetic engineering. Single base pair substitutions can have significant clinical implications, such as in the detection of single nucleotide polymorphisms (SNPs) and genetic diseases caused by mutations.