What Is $t ^ { 3 } \cdot t ^ { 3 }$

Multiple Choice

What is $t ^ { 3 } \cdot t ^ { 3 }$  rewritten using only one exponent?

A) $t ^ { 0 }$
B) $t ^ { 6 }$
C) $t ^ { 3 }$
D) $t ^ { 9 }$
E) none of these