Open 2"-3" ABS pipe in Basement - Dripping

Hi, new to the forum.

I have a 5 year old home. In the basement there is a black abs pipe descending from the floors above which is open and cutoff at about 10" below the main floor. When it rains water drips out of the pipe. Is this a vent stack that needs to be connected to the plumbing associated with and adjacent utility sink that was installed after we moved in? (not by me)

If so what do I need to be aware of or what do I need to tell a plumber and how much should it cost?

Thanks

It sounds like a future vent. Some plumbers want it left open so the water doesn't fill the pipe up and make it hard to open in the future. Some plumbers want it closed so you don't get dripping from it.
I would not make it any shorter than it is. I would just put a cap on it and leave it alone till it is need in the future.

If it is collecting rainwater, it's extending through the roof. I'd cap it on the roof so water wouldn't get in and collect. If and when the time comes you needed it as a vent, just cut the cap off. the couple of inches lost would not be significant.

pipe

I would glue a male adapter on the end and then screw a cap onto it. IF it is ever needed it could be full of water and it will be easier to remove a cap and drain it then to try cutting it off with the water in the pipe.