Choosing a training unlock some ability

After watching the polygon stream (1st hour of gameplay), I discover than during the CC we choose one training background.
That training background gives us our first ability and unlock two abilities. We don't have information if those ability could be later unlock.

so I put them here with in order name of the training - start ability - unlocked abilities

Security - Concussive Shot - Turbocharge and Combat Fitness
Biotic - Throw - Singularity and Barrier
Technician - Overload - Invasion and Team Support
Leader - Energy Drain - Annihilation and Team Support
Scrapper - Charge - Combat Fitness and Charge
Operative - Tactical cloak - Combat Fitness and Tactical Cloak

That is why there were some greyed option in the gameplay serie.
I'm going to take the vanguard scrapper training, what will you take ?