A 32-year-old woman was stung by a wasp. The site of the sting is edematous and hyperemic. What is the primary mechanism of edema formation in this case?

Answer options

1. Increased interstitial fluid oncotic pressure
2. Increased capillary permeability
3. Problematic lymphatic efflux
4. Increased blood hydrostatic pressure in the capillaries
5. Decrcascd blood oncotic pressure