A temporary gust of wind from an angle to the left of the aircraft, manoeuvers the aircraft directionally left.
If the aeroplane has strong directional stability, it will adopt a final direction that is:
(a) towards the disturbance
(b) somewhere between the original and the disturbance
(c) the same as the original

I don't know how to answer this.
(a) and (b) seem identical to me.

Yaw, followed by roll, obviously causes a direction change. But the extent of that change would depend on how long the temporary disturbance lasted. If it was very short and the gust was relatively mild, I'd say, (c) the same as the original, especially if the aircraft has very strong directional stability. However, if the gust is particularly strong or lasting 15 seconds or so, I'd answer (b). (a) is a bit too vague for my liking.

At this point, because I can't distinguish the meaning between (a) and (b), I'd choose (c).

Am I thinking this right?

Well it's certainly not one of our questions. I agree that the wording leaves something to be desired. If the aircraft adopts a final direction that is the same as the original does that meant before the gust hit. If so, it means the gust had no effect. If I had to choose, I'd pick (a) as the safest bet. But don't loose any sleep over it.