Which of the following routes requires aseptic technique to prevent infection?

The intradermal injection route requires aseptic technique to prevent infection because it involves the administration of medication directly into the dermis, which is just below the outer layer of skin. This procedure creates a break in the skin barrier, making it critical to use sterile equipment and maintain a clean environment to reduce the risk of introducing pathogens that can lead to infections.

The need for aseptic technique is heightened in this route due to the potential for direct exposure of internal tissues to external contaminants during the injection process. The other routes mentioned, although they might require some level of cleanliness, do not involve piercing the skin and thus have a lower risk of introducing microbes directly into body tissues.