A. This is not the answer because all four sides of a rhombus are the same length. We can rule out choice A
B. This is the answer because we can eliminate choice C and D. A trapezoid could have all four sides that are different in length as long as its not isosceles.
C. An isosceles triangle has two sides that are the same length so we can rule this out
D. All three sides of any equilateral triangle are the same length, so we can rule this out.
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So once again, the answer is choice B
