How to reply to a show cause notice?

I am female& work in a community service renowned NGO in Delhi hospital as Superintendent of Nursing since last 1.5 years . I earlier retired as class 1 officer in Ctrl.Gov after 30 years of spot less service. The new hospital Supdt joined 2.5 months back is hostile and makes personal remarks & disrespectful language and promotes lower employees & bypassing. He called me liar.On protesting He has now issued Show cause notice after 5 days for using foul language to employees in past regularly and my incompetence in work.My work is good.Only issue is indiscipline and bypassing.Looks he wants to bring own person. So how to handle this notice and what is seriousness of it.There is loose govt control on hospital which he is misusing.Earlier no warning letter ever issued.Factually it is malicious and preemptive for likely complaint by me to top. I view it as gender discrimination and contempt by this arrogant person.