<prompt> What is the mechanism by which the following technique works?CryotherapyPositive pressureNegative pressureSclerotherapy  <response>: Ans. C Negative pressureRef: Bailey Loves Short Practice of Surgery 27th Ed; Page No-30Negative Pressure dressing VAC dressing which exertsa pressure of -125 mm Hg and hastens wound healing in chronic wounds.It can be used for:Venous ulcer without sloughBurns wounds without escharBedsores without sloughDiabetic foot ulcer without osteomyelitis 