Let $f ( x ) = ( x + a ) \ln ( x + b )$. If $f ( x ) \geq 0$, then the minimum value of $a ^ { 2 } + b ^ { 2 }$ is A. $\frac { 1 } { 8 }$ B. $\frac { 1 } { 4 }$ C. $\frac { 1 } { 2 }$ D. 1
Let $f ( x ) = ( x + a ) \ln ( x + b )$. If $f ( x ) \geq 0$, then the minimum value of $a ^ { 2 } + b ^ { 2 }$ is\\
A. $\frac { 1 } { 8 }$\\
B. $\frac { 1 } { 4 }$\\
C. $\frac { 1 } { 2 }$\\
D. 1