ladies please help. my husband and I are separated at this moment. I'm expecting to have his child.…

ladies please help. my husband and I are separated at this moment. I'm expecting to have his child. we haven't spoken since the separation. he just emailed me and asked if the child I'm carrying his? how do I respond? I take a huge offense to such a question. I have been 100% faithful to him up until this point. this question really upsets me. how do o respond to this?