The correct option is D 0
Given:
y−z∝1x,z−x∝1y and x−y∝1z
y−z=k1x.eq(1)
z−x=m1y…eq(2)
x−y=n1z..eq(3)
Where k,m and n are constants,
Adding all the three equations we get,
y−z+z−x+x−y=(kx+my+nz)
⇒0=(kx+my+nz)
Now, k,m, and n are also constants.
Then, the sum of these variation constants will also be 0