One will protect you. The rest will try to kill you.

You find yourself on a space station in the Mass Effect universe, running for your life. One individual will do everything in their power to ensure your survival and escape. However if they are killed, you're on your own.

Who will you choose to protect you?

Who in their right mind would pick a vorcha or batarian?  Or krogan merc, unless you've got a big wad of cash.

If im going out im going out with a bang

The Turian.

They live in a militaristic society and are trained for war and all possible outcomes. The fact that he's Spec Ops suggests he is one of the top ranking soldiers within this warrior society and that he is proficient in all forms of weaponry while also being capable of adapting to a variety of environments.

Depending on what rank they are, the Alliance Marine probably fits into this category as well.

I was originally going to put down Asari Commando , seeing as how she's one of the only biotics on the list, which would obviously be useful, even moreso in-universe than in gameplay.

However, I decided to choose the Geth Trooper , on the grounds that it would have considerable aiming skills, physical strength, impressive barriers, and cold logic. Its hacking abilities would be imperative to this specific situation as well, considering you may need to unlock (or lock) doors, etc.

Note, however, that this choice would only be taken after Geth/quarian peace, and the Geth's upgrade. Otherwise, a single trooper would be fairly useless, and I would go back to my original choice, the asari. As a popular turian saying puts it, "The asari are the finest warriors in the galaxy. Fortunately, there are not many of them."

I say Alliance Marine they can hold out enough for me to escape. After all they are the Stormtroopers of ME3 imo.

Salarian STG on grounds that beyond being top trained and proficient in a wide variety of tech they also seem used to Ops and situations where they are outnumbered.

The Turian for me :)

outside the box.....

Alliance Marine cos everyone is out to kill humanity after the ass pull mass effect 3 ending.

STG, the battle is won before the enemy knew they were fighting

Geth trooper because it took friggin Shepard to push through them to reach Saren :P

 EDIT: Mind you this is a powerful trooper, not a grunt. Same with all the other options.

Asari Commando. Remember Wrex's story, and Wrex is one of the baddest krogan around... Hard to say, Wrex would be great to protect you, and if it were an Asari against every other 'hero' we know from ME, such as Garrus or Wrex for those two options... you're screwed no matter which way you try and pick, IMO anyway.