Zoe is calculating the volume of this rectangular prism. 
Zoe calculates the volume as 16 cubic units because 8 units long + 5 units high + 3 units wide = 16 cubic units.  Which of the following describes the mistake Zoe made in her calculation?

Zoe is wrong because she calculated the volume 8 + 5 + 3 = 16 instead of 8 × 5 + 3 = 43.
Zoe is wrong because she added all the dimensions instead of only adding the length and width.
Zoe is wrong because she calculated the volume 8 + 5 + 3 = 16 instead of 8 + 5 – 3 = 10.
Zoe is wrong because she added all the dimensions instead of multiplying all the dimensions.
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