How to find features those are intersected by a feature in ArcMap python/C#

Hi

I have some feature classes in ArcMap (Line, point types). I need to search by selected a feature (such as a point), that which ohter features in the ArcMap intersect that point feature. I need to build a script in python or a C# code to solve this. Could you please advice how to do that.

Thanks
Naym