The Equation of the Line Tangent to the Graph Of f

The equation of the line tangent to the graph of $f ( x ) = 3 \sqrt { x }$ at x = 1 is

A) $y = \frac { 1 } { 2 } x - \frac { 1 } { 2 }$
B) $y = \frac { 1 } { 2 } x + \frac { 1 } { 2 }$
C) $y = \frac { 3 } { 2 } x + \frac { 3 } { 2 }$
D) $y = \frac { 3 } { 2 } x - 1$