Prehybridization solutions in SSC are used to block nonspecific binding sites on membranes during nucleic acid hybridization procedures. They help reduce background noise by preventing the probe from adhering to the membrane or tissue sections nonspecifically. This step is critical in techniques like Southern blotting, Northern blotting, and in situ hybridization. The SSC buffer maintains appropriate ionic strength, ensuring optimal conditions for hybridization. By using a prehybridization solution, the specificity and sensitivity of the hybridization reaction are significantly improved, leading to more accurate and reliable detection of target DNA or RNA sequences.