Comprehension . \( \quad \) The vertices of \( \triangle A B C \) are \( A(2,0,0), B(0,1,0), C(0...

Comprehension . \( \quad \) The vertices of \( \triangle A B C \) are \( A(2,0,0), B(0,1,0), C(0,0,2) \). Its orthocentre is \( H \) and circumcentre is \( S . P \) is a point equidistant from \( A, B, C \) and the origin \( O \).
The \( y \)-co-ordinate of \( \mathrm{S} \) is
(a) \( 5 / 6 \)
(b) \( 1 / 3 \)
(c) \( 1 / 6 \)
(d) \( 1 / 2 \)