## Core Concept
Delayed wound healing can be caused by various factors, including nutritional deficiencies, chronic diseases, and certain medications. Understanding the underlying causes is crucial for proper management and treatment. Wound healing involves complex processes, including inflammation, proliferation, and remodeling.

## Why the Correct Answer is Right
Zinc is an essential trace element that plays a significant role in wound healing. It is involved in various aspects of the healing process, including inflammation, tissue repair, and protein synthesis. Zinc deficiency can impair wound healing, leading to delayed recovery.

## Why Each Wrong Option is Incorrect
* **Option A:** Diabetes mellitus is known to cause delayed wound healing due to neuropathy, peripheral arterial disease, and poor glycemic control, which impair the healing process.
* **Option B:** Malnutrition, including deficiencies in vitamins and minerals, can significantly affect wound healing by impairing collagen synthesis, tissue repair, and immune function.
* **Option D:** Steroids, or corticosteroids, can delay wound healing by suppressing inflammation, which is a crucial step in the healing process, and by affecting collagen synthesis and tissue repair.

## Clinical Pearl / High-Yield Fact
A key clinical pearl is that zinc supplementation can enhance wound healing in patients with zinc deficiency. Clinicians should consider assessing and correcting nutritional deficiencies, including zinc, in patients with delayed wound healing.

## Correct Answer: C.