Hey, I want to know what is the future of Adobe Illustrator and Adobe Photoshop in UI Design? Does Adobe XD will be standard and going to replace photoshop and illustrator in UI designing?
It works in tandem with Photoshop and Illustrator.
It’s used in creating a the UI/UX experience - and you use other tools alongside it.
From what I understand by those links that Adobe Illustrator and Photoshop can be used as Icon, assets and other content creation which then can be used in Adobe XD to create the UI. However, still it failed to provide my question answer will it be standard in UI design and replacing the Adobe Illustrator and Photoshop completely from UI design?
Only if you want to work that way.
Illustrator and Photoshop are used for far more other things than UI.
If you want to just use XD as your tool, go for it. I seriously doubt the other two will be dropped any time soon.
I doubt even Adobe employees could answer the question definitively.
I will say this: Historically, it isn’t Adobe’s “style” to outright supplant their own applications with others. A much more common strategy is to partially duplicate feature sets to varying degrees across applications. This allows users greater flexibility (sometimes to negative effect) in devising workflows to suit their objectives and preferences.
In a way, this renders your question flawed in that it asks about what is, and what will be (the) “standard”. I’d be inclined to infer that Adobe’s mixed-features approach has resulted in “standard” becoming a weakening concept, and one user’s “standard” will be different from another’s. This is evident if you follow the core applications on Adobe’s user forums, where you’ll see a steady stream of users whose deliverable is a raster image, but they started in Illustrator and ran into problems rooted in Illustrator’s crappy raster export features, for example.
There’s no answer to that. I know people that supply AI for UI designs, I know people that supply PS as UI design. I know people that supply XD as UI design.
I know people that supply Powerpoint as UI design. I know people have submitted UI design in MS Paint.
People will use whatever tools they can to create what they need. XD is just another tool - I can’t see it replacing any definitive workflow.
From what I understand from these responses that it is depended on the organization/workplace what they are using for UI Design. It can be Adobe Illustrator, Adobe Photoshop, Adobe XD or any other software such as Figma.
Please don’t tell me this was all a leadup to an ad for Figma. 
I am the user of Adobe Illustrator and Adobe Photoshop till date I have not used any other tool for UI design creation. Sure I have used other mock up tools such as Pencil Project, Balsamiq but never for UI design. I have just mention Figma tool just for the example I can also mention other tool example such as AXURE RP PRO.
I think XD shows its strength in workgroup situations where there are divisions of duties that take advantage of XD’s way of doing things. For example, if there are multiple people involved in a job from a UI designer to a backend developer and everything in between, XD can be very useful.
However, different situations require different approaches, A single person building a site from scratch or a developer modifying an already-existing Drupal template might not find XD especially useful.
In addition, how many prototyping competitors to XD are there now — a dozen or two? The way that I look at it, XD isn’t a wholesale replacement for anything. It’s just another situationally useful tool.