Yes, it's A.
A is the only option that is not instinctual. Riding a bicycle is something that has to be taught (and even if you weren't taught to ride a bike, you had to figure it out by trial and error.)
The other options are instinctual and reflexive responses. The salmon returning to the river is a behavior that is pretty much hard-wired into the salmon's brain. The plant turns to follow the sun because it is a source of light and energy.
The other user expressed uncertainty as to option D, but in fact, option D is very much a reflexive, instinctual response as well. To flinch or blink when something abruptly moves towards you is not a choice or something you have to be taught — it's a reflex, something you can't control.