Simplify the given expression.
(1+3i)+(2-5i)

a)-1 - 2i
b) 3 - 2i
c) 4 - 3i
d) 5+6i

im really confused can someone me solve it?

Since you can only perform addition and subtraction on variables that have the same variable following them, the correct answer is B. 3 - 2i.
Here's why:
1 + 2 + (3i - 5i) =
3 - 2i

(1 + 3i) + (2 - 5i) = 1 + 3i + 2 - 5i = 3 - 2i