The correct answer is - reduced thoracic (lung) compliance.
Explanation:
Reduced lung compliance is characterized by the stiffness in the lung and required extra work to internalize normal volume of the air in the thoracic cavity.
It is caused as the lungs, in this case, are become fibrotic, become stiffer and distensibility. Due to the enzyme activity elastic tissue becomes damaged in case of emphysema in highly compliant lungs.
Thus, the correct answer is - reduced thoracic compliance.
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