Yes you are eligible for acms Delhi as your father was an ex-serviceman .

The admission to the ACMS is for the children of eligible serving Army personnel, Ex Army personnel and war widows/widows of the Army. The children of following categories of Army personnel are eligible and they are required to submit the relevant certificate as given against the category applicable to them as proof of their eligibility for admission to ACMS at time of Counseling/Admission

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