There is bomb on top of a computer; around the computer are a hairbrush, keys, phone and a cup. When the explosion comes, what item destroyed first?

Common Wrong Answers
“The computer”
While the computer is directly underneath the bomb, it is not the first item to be destroyed. The bomb itself detonates first.
“The cup”
The cup is not in direct contact with the bomb and would likely be destroyed by the explosion, but it is not the first item affected.
“The phone”
Similar to the cup, while the phone may be damaged in the explosion, it is not the first item to be destroyed since the bomb detonates first.
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