Solve the Problem $f ( x , y , z ) = \sqrt { x ^ { 2 } + y ^ { 2 } + z ^ { 2 } }$

Multiple Choice

Solve the problem.
-Find an equation for the level surface of the function $f ( x , y , z ) = \sqrt { x ^ { 2 } + y ^ { 2 } + z ^ { 2 } }$ that passes through the point $( 3,12,4 )$ .

A) $x + y + z = \pm 13$
B) $x ^ { 2 } + y ^ { 2 } + z ^ { 2 } = 13$
C) $x + y + z = 13$
D) $x ^ { 2 } + y ^ { 2 } + z ^ { 2 } = 169$