Final answer:
LCR stands for Ligase Chain Reaction, which is akin to Polymerase Chain Reaction (PCR), a technique used to amplify DNA. Therefore, the correct option is 1.
Step-by-step explanation:
The acronym LCR stands for Ligase Chain Reaction. It is a method similar to the more commonly known Polymerase Chain Reaction (PCR), which is used for the amplification of DNA. The PCR cycle includes three main steps: denaturation, annealing, and DNA synthesis. During denaturation, the DNA strands are separated by heat. During annealing, primers bind to the specific sequences on the DNA strands that need to be copied. In the extension or DNA synthesis step, a DNA polymerase enzyme synthesizes new strands of DNA complementary to the original strands, effectively doubling the amount of DNA. These cycles are repeated many times to amplify the target DNA segment exponentially. While PCR uses thermal cycling to denature and anneal DNA, LCR involves joining two DNA strands with a DNA ligase and amplifies DNA at a constant temperature.