Add or Subtract $\sqrt { 98 } - 3 \sqrt { 8 } + 9 \sqrt { 128 }$

Multiple Choice

Add or subtract. Assume all variables represent positive real numbers.
- $\sqrt { 98 } - 3 \sqrt { 8 } + 9 \sqrt { 128 }$

A) $- 73 \sqrt { 2 }$
B) $- 8 \sqrt { 2 }$
C) $- 4 \sqrt { 2 }$
D) $73 \sqrt { 2 }$