What is the value of the result variable after the code below is executed?

one $={?}^{\text{'}}{1}^{\text{'}}$

two $={?}^{\text{'}}2\text{'}$

result $=$ one $+$ two

result $+={?}^{\text{'}}3\text{'}$

$\text{'}6\text{'}$

$15$

$6$

$\text{'}123\text{'}$