Can we be racist? [in Andromeda]

You can be casual, logical, professional, or emotional. (and impulsive if you include interrupts).

I don't think 'be racist' falls into any of those categories.

'Racist' comments can be made under any of those categories.
You can be 'casual' about the inferiority of the Krogan; talk about it jokingly, etc.
You could deduce the inferiority of the Turians from a bunch of false premises (hey, as long as it's a valid deduction [does this conclusion follow from these premises?], you're logical enough).
You could put forward 'professional' reasons for holding back the Asari, and promoting the Human.
or, you could make emotional speeches about human supremacy (pick any emotion you like, rage, elation, etc.)

I hope there will be Batarians in ME:A so i can massacre'em all =)

I would assume you could, but it would be done indirectly through Investigation options such as in ME1 when you asked why you bothered giving the Turians intel.

No I don't think we can, not unless it's part of another character but they won't let the player spout politically incorrect ideas I don't think.

Btw why is there an Asari in the human Ark? 

Nope. This is a alien-banging simulator, not a alien-hating simulator. Carry on.

Better question is why isn't a human doctor looking at Scott instead of the asari?

And why does she have access to Sam which has access to everything Pathfinders experience? 

Speciesist... at most, and I doubt people holding such views would join an organisation as the Ai.

I'm sure Bioware's answer will be play the game

While I probably wouldn't use the racist dialogue options much and don't expect that they would add them in, I do hope that Andromeda will let be me be more of a dick to people than Inquisition did.

Although I'm expecting Inquisition levels of "you can sometimes be a dick, but you gotta be paragon overall"