The C in COPD stands for:

A. Compliant is not the term used in COPD. It refers to something that is flexible or yielding, which does not describe the condition.
B. Cumulative could describe the long-term effects of COPD, but it is not the word represented by the "C" in COPD.
C. Congestive is a term often associated with conditions like congestive heart failure, not COPD.
D. Chronic is the correct term. Chronic Obstructive Pulmonary Disease (COPD) refers to a long-term, progressive lung disease that causes difficulty breathing due to airflow obstruction.

A. A small amount of carbon dioxide is transported dissolved in plasma, but this accounts for only about 5–10% of the total CO₂ in the blood.
B. Some carbon dioxide binds to hemoglobin to form carbaminohemoglobin, but this form carries only about 20–30% of CO₂.
C. Albumin primarily transports hormones, fatty acids, and other substances—not carbon dioxide.
D. The majority of carbon dioxide (about 60–70%) is carried in the blood as bicarbonate ions (HCO₃⁻). This occurs through a reaction where CO₂ combines with water to form carbonic acid, which then dissociates into bicarbonate and hydrogen ions.