The set T={(x,y,z)∣(x−1)2+(y+2)2+z2≥49} describes which region in space?
a) Only the spherical surface of radius 7 centred at (1,−2,0)
b) The exterior (including surface) of a sphere of radius 7 centred at (1,−2,0)
c) The interior (including surface) of a sphere of radius 7 centred at (1,−2,0)
d) The exterior (including surface) of a sphere of radius 7 centred at (0,0,0)