keyhole question

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The figure would be flipped upside down and you would be looking at the end view and passing it through that way.

It can't be B and D because it needs to be a combination of both.

It can't be C because there is no 3rd layer on top

It can't be E because the "protruding" portion on the bottom can't be there

Basically this section is also a top front end section. I figure out the 3 sections of this view and eliminate each 1 of the answers based on what can't be there.
 
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