Find the Cotangent (If It Exists) of the Real Number $t = - \frac { 5 \pi } { 4 }$

Multiple Choice

Find the cotangent (if it exists) of the real number $t = - \frac { 5 \pi } { 4 }$ .

A) $\frac { \sqrt { 2 } } { 2 }$
B) $- 1$
C) 1
D) 0
E) $\cot \left( - \frac { 5 \pi } { 4 } \right)$ does not exist