The question asks to identify which given equations represent circles, determine when a general equation represents a circle, or classify the curves represented by a system of equations.
| (A) | $S$ is a circle with centre $\left( - \frac { 1 } { 3 } , \frac { 10 } { 3 } \right)$ |
| (B) | $S$ is a circle with centre $\left( \frac { 1 } { 3 } , \frac { 8 } { 3 } \right)$ |
| (C) | $S$ is a circle with radius $\frac { \sqrt { 2 } } { 3 }$ |
| (D) | $S$ is a circle with radius $\frac { 2 \sqrt { 2 } } { 3 }$ |