Which of the following is a true statement? A. All epithella separate inside from the outside. B. The linings of the cardiovascular system separate inside from outside. C. Most epithelia separate inside from outside. D. none of the above

Step 1: Define the Problem

Identify which statement about epithelia and their function in separating inside from outside is true.

Step 2: Break Down the Problem

Evaluate each statement:

• A. All epithelia separate inside from the outside.
• B. The linings of the cardiovascular system separate inside from outside.
• C. Most epithelia separate inside from outside.
• D. None of the above.

Step 3: Apply Relevant Concepts

• Epithelia: Tissue that covers the body surfaces, lines body cavities, and forms glands. It often serves as a barrier.
• Cardiovascular System Lining: The endothelium is a type of epithelium that lines the cardiovascular system.

Step 4: Analysis, Verify and Summarize

• Statement A: Not all epithelia separate inside from outside; some have other functions, such as absorption or secretion.
• Statement B: The endothelium lines the cardiovascular system but does not separate inside from outside in the traditional sense, as it is part of the internal environment.
• Statement C: Most epithelia do serve as a barrier, separating different environments, such as inside from outside.
• Statement D: If none of the above statements are true, this would be the correct choice.

Final Answer

C. Most epithelia separate inside from outside.