Final answer:
Alginate dressings are used to promote healing by causing debridement and encouraging granulation in the wound bed. Antiseptics are suitable for microbial control to prevent infection. Hydrogen peroxide can support healing but poses a risk of gas embolism if used surgically.
Step-by-step explanation:
The dressing that promotes healing by causing debridement and allowing granulation of the wound bed is Alginate dressings (C). Alginate dressings are highly absorbent and encourage a moist healing environment. They assist in autolytic debridement and are ideal for wounds with significant exudate. The dressings facilitate the formation of granulation tissue, necessary for the healing process. For microbial control to prevent infection, the suitable substance to use on tissues is B. antiseptic.
Regarding H₂O₂, it can induce healing if it's not repeatedly applied; however, its surgical use can lead to gas embolism formation. It is popular as a first aid antiseptic but should be used with caution. When managing infections like gas gangrene, diagnosis is confirmed through Gram stain and anaerobic cultivation of wound exudate, and treatment involves antibiotics such as penicillin G and clindamycin, surgical debridement, and possibly hyperbaric oxygen therapy.