Given the following activity network: A$1-$A$2-$A$3,$ A$1-$A$3,$ where activity A$1$ takes $5$ weeks, A$2$ takes $8$ weeks, and A$3$ takes $2$ weeks.

What is the earliest completion time of A$2?$

Question $39$ options:

A$)$

$13$ weeks

B$)$

$10$ weeks

C$)$

$15$ weeks

D$)$

$5$ weeks