Question

PLEASE HELP IM LITERALLY SO STRESSED RIGHT NOW. pleaseeeeeeee :(((

Answer 1

B is the right answer because you can set up a ratio like this:
$tan(A) = (\frac{16.3}{16.3})$

If you solve for A, then you get:
$A = tan^-1(\frac{16.3}{16.3})$ 

Hopefully this makes sense. Also, in the textbox, ∠A = 45° and your answer's B.