## **Core Concept**
Hemopexin is a plasma protein that binds heme with the highest affinity among plasma proteins. This binding is crucial for protecting the body from the oxidative damage that free heme can cause. Heme is a breakdown product of hemoglobin.

## **Why the Correct Answer is Right**
Hemopexin binds heme with high affinity, which helps in reducing oxidative damage and facilitating the recycling of iron. This protein plays a significant role in the conservation of body iron and protection against heme-mediated oxidative damage.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because although albumin does bind a variety of substances, including some drugs and bilirubin, it is not the primary binder of heme.
- **Option B:** This option is incorrect because while ceruloplasmin is involved in copper transport and has ferroxidase activity, it is not primarily known for binding heme.
- **Option C:** This option is incorrect because although hemoglobin does contain heme, the question pertains to a plasma protein that binds heme, not the hemoglobin itself.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that haptoglobin and hemopexin are both involved in binding and recycling of hemoglobin and heme, respectively. Hemopexin's role is critical in preserving iron and mitigating oxidative stress.

## **Correct Answer:** D. Heme.