Objective question in Biology

The lungs are enclosed by a double-layered membrane which is called a) Pleura b) Bronchi c) Pericardium d) None of the above

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∑ ∑ ∑ ∑ ∑ ∮ ∮ ∮ ∮ ∮ ∏ ∏ ∏ ∏ ∏ ∐ ∐ ∐ ∐ ∐

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