Consider the following four statements (A-D) about aves (birds) and select the correct option stating which ones are true (T) and which ones are false (F). 

A. Hindlimbs are modified into wings 

B. Oil gland is present at the base of the tail 

C. Endoskeleton is not ossified 

D. Air sacs are connected to the lungs

	A	B	C	D
1	F	F	T	T
2	T	T	F	F
3	F	T	F	T
4	T	F	T	F