PAT Keyhole: Silhouette projection or Actual Aperture

[RSD2014]

(This shape I made up to show a point)
Are the answer choices silhouette projection of the original structure or Actual "aperture (hole)"?

My understanding is that the answer choices are "aperture" in which the original structure can pass through.

In this case, Choice A (actual aperture) would be best choice because the "aperture (hole)" is big enough to accommodate the entire structure.
In Choice B (would be a silhouette projection), why would we need a hole in the middle? if the outer shape is big enough for the object to go through?

According to Crack PAT, choice B would be the answer.
If Choice B were the answer, wouldn't the answer be "silhouette projection" of the original structure, instead of "aperture"?

ADA Rule: "The opening is always the exact shape of the appropriate external outline of the object"

These type of questions can be seen in CRACK PAT Test4 #12 (between Choices D & E).
CRACK PAT Test5 #4 (between Choices B & D)


Edited: Nevermind, I figured it out. It's called "keyhole" for a reason.

---

Members don't see this ad.

 

[LuckMC11]

for the question u put, it would be the 2nd one as the choice. if there is a clear hole through and through, it would have to go through whatever answer choice you pick (that is if you chose that specific viewpoint of how it would go through, like Top/bottom, front/back, or side/side). but you could also get an opening from side/side (so it would look like an L), and if that was the case you would just have to distinguish from minor details they will/could include, like the bottom of the L (like the _ is smaller than the |) or not things like that

 

[RSD2014]

for the question u put, it would be the 2nd one as the choice. if there is a clear hole through and through, it would have to go through whatever answer choice you pick (that is if you chose that specific viewpoint of how it would go through, like Top/bottom, front/back, or side/side). but you could also get an opening from side/side (so it would look like an L), and if that was the case you would just have to distinguish from minor details they will/could include, like the bottom of the L (like the _ is smaller than the |) or not things like that

The reason I post this question is that Crack PAT has questions that come down to those 2 choices. One with an opening in the middle, while the other does not.

My question is, why would the internal cut-out be relevant if the ADA Rule stated that the "opening" is the exact shape as the "external outline."

 

[LuckMC11]

i think that external outline thing its talking about includes the internal cut out, and disregards any projections or figures protruding an object like directly on the object, as is shown on many objects. like if there is a spike coming out, dont worry about the spike affecting the answer if it fits properly with the "external" outline of the 3D object being used