what component is secured to one side of the stringer below the cut notches to add strength and…

what component is secured to one side of the stringer below the cut notches to add strength and rigidity?\nguard\nskirtboard\ngooseneck\nstrongback
Answer
Brief Explanations:
In construction - related knowledge, a strongback is secured to one side of the stringer below the cut notches to add strength and rigidity.
Answer:
D. strongback