Multiply the Radicals with Different Indices $\sqrt [ 4 ] { 7 } \cdot \sqrt { 7 }$

Multiple Choice

Multiply the radicals with different indices. Write the answer in radical form and simplify. $\sqrt [ 4 ] { 7 } \cdot \sqrt { 7 }$

A) $\sqrt [ 8 ] { 7 }$
B) $\sqrt [ 4 ] { 49 }$
C) 7
D) $\sqrt [ 4 ] { 343 }$