Unilateral elevation of diaphragm is commonly due to – a) Obesityb) Large liverc) Scoliosisd) Congenital causes
Scoliosis can cause unilateral elevation of hemidiaphragm.
Obesity and hepatomegaly cause bilateral elevation of hemidiaphragm.

Option 'b' requires specific mention here :-
Hepatomegaly (large liver) causes bilateral elevation of hemidiaphragm because normal liver is under both the dome of diaphragms. Therefore, enlargment of whole liver (hepatomegaly) causes bilateral elevation of hemidiaphragm. However, involvement of a part of liver (e.g. liver abscess) causes unilateral elevation of hemidiaphragm.
a
c
bc
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