Which is the right answer

The vector perpendicular

to OA and OB where O ,A,B are points with coordinates (0,0,0),(3,6,1),(1,2,3) in order is of the form xi+yj which option gives the value of x and y
A. X=-16 , y=-8
B . -8,16
C. -20,-10

D. -10,20
E. -16,8
F. 16,8
G. 10,-20
H. 20 ,10 can you show work please

with given coordinates the vector OA--> (I mean OA is the +ve direction) = (3-0) i + (6 - 0) j + (1 - 0) k, where i,j and k are unit vector in the three mutually perpendicular direction referred to the coordinate axes.
So OA--> = (3-0) i + (6 - 0) j + (1 - 0) k = 3 i + 6 j + k....................(1)

Similarly, OB--> = (1-0) i + (2 - 0) j + (3 - 0) k = i + 2 j + 3 k .............(2)

Let OP--> be the vector perpendicular to both OA and OB be

p--> = l i + m j + n k ........................................…

Since vector 'p' given by (3) should be perpendicular to both (1) and (2) so the orthogonality condition needs

3 l + 6 m + n = 0.........................(4)

and l + 2 m + 3 n = 0.........................(5)
solving simultaneously equations (4) and (5) ( I forgot, is it componedo - dividendo rule??)

[ l/(18-2) = m / ( 1-9) = n / (6-6)
==> l/16 = m/-8 = n /0

Hence your solution should be

16 i - 8 j

i.e., your answer is -- A