Which of the following is/are a duties of National Commission for Backward Classes?

A.To enquire into specific complaints with respect to the deprivation of rights and safeguards of the socially and educationally backward classes

B.To participate and advise on the socio-economic development of the socially and educationally backward classes

C.To discharge other functions in relation to the protection, welfare, development and advancement of socially and educationally backward classes

D.All of the above