The plumbing drainage is roughed in my unfinished basement. I recognize the shower/tub drain and the toilet drain. There are two 2" pipes coming out of basement floor one on each side of toilet drain. One has to be for the sink but not sure what the other is for. Any help would be appreciated. I have attached a picture.

Thanks

From the looks of the pic you provided they all look like drains. I could be wrong.
Are you the first owner? What are you hocked up to? (I.E. City wast or siptic system) Need more info to help you out.

That hole isn't for a shower, it's for a bathtub and is called "the tub dap-out". Dig down in that hole and you should find a trap and raiser down there. If you do not find one then the plumber has missed his measure and the trap and raiser is the pipe in question. However, This isn't all bad if you're planing on installing a shower. Simply fill and run a cement patch on the dap-out and you're ready to install a custom tile shower or a manufactured one. The other 2" pipe is for the lavatory and is also the vent for your bathroom group. Good luck, Tom