Planes in R^3

Which one of the following is the standard form equation of the plane in R3\reals^3 which contains the lines (x,y,z)=(2,0,1)+t(2,5,1)(x,y,z)=(2,0,-1)+t(2,-5,-1) and (x,y,z)=(3,1,2)+t(3,5,1)(x,y,z)=(3,1,2)+t(3,-5,1)
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