Perform the Indicated Operations $$\frac { x ^ { 1 / 2 } } { x ^ { 3 / 4 } \cdot x ^ { - 4 } }$$

Multiple Choice

Perform the indicated operations. Write the answer using only positive exponents. Assume all variables represent
positive real numbers.
- $$\frac { x ^ { 1 / 2 } } { x ^ { 3 / 4 } \cdot x ^ { - 4 } }$$

A) $\frac { 1 } { x ^ { 21 / 4 } }$

B) $\frac { 1 } { x ^ { 15 / 4 } }$

C) $x ^ { 21 / 4 }$

D) $x ^ { 15 / 4 }$