Five choices I made up:

**a.**![enter image description here][1]
**b.**![enter image description here][2]
**c.**![enter image description here][3]
**d.**![enter image description here][4]
**e.**![enter image description here][5]

One thing I know immediately is that the vectors have to cancel each other at last so there is no net force acting on it.

**a.** certainly qualifies.

**b.** doesn't. If the components of the vertical arrow leave the object sliding down the incline.

**c.** has two vector forces directed down the incline, but only of which is is cancelled.

##d. is tricky. 
There is a unbalanced force going into the plane. But that vector won't change the fact that the object is at rest. One would automatically realized there is a normal force preventing the object from falling into the plane.

**e** is basically the same as **c**, except that the normal force isn't drawn.

______
If the cause of my confusion still isn't clear to you, it is that I can't settle between choices **a** and **d**, due to the lack of the normal force in **d**.


  [1]: https://i.sstatic.net/2MA3B.jpg
  [2]: https://i.sstatic.net/JrSNA.jpg
  [3]: https://i.sstatic.net/EqajT.jpg
  [4]: https://i.sstatic.net/aEZJ9.jpg
  [5]: https://i.sstatic.net/VFMOg.jpg