Identify the Open Intervals Where the Function $f ( x ) = 4 x ^ { 2 } - 5 x - 5$

Multiple Choice

Identify the open intervals where the function $f ( x ) = 4 x ^ { 2 } - 5 x - 5$ is increasing or decreasing.

A) decreasing: $\left( - \infty , \frac { 5 } { 8 } \right)$ ; increasing: $\left( \frac { 5 } { 8 } , \infty \right)$
B) increasing: $\left( - \infty , \frac { 5 } { 8 } \right)$ ; decreasing: $\left( \frac { 5 } { 8 } , \infty \right)$
C) increasing on $( - \infty , \infty )$
D) decreasing on $( - \infty , \infty )$
E) none of the above