In COPD which is true: (A) FEV1/FVC <0.7, (B) FEV1/FVC (upward arrow), (C) RV (downward arrow), (D) TLV (downward arrow)
Answer is A. COPD is characterised by reduced FEV1 with a reduction in FEV1/FVC ratio less than 0.7.With worsening disease severity,lung volumes may increase,resulting in an increase in TLC,RV and FRC. Reference:Harrison's medicine-18th edition,page no:2156.