Answer:
A.

Explanation:
To simplify the expression (4x3y + 5xy2 − 2xy) + (6x3y − 9xy2 + 3xy), you can combine like terms. Like terms are those that have the same variables raised to the same powers.
Let's go step by step:
First, let's add the coefficients of the terms that have the same variables and powers.
The terms with "
":
+
=

The terms with "
":

The terms with "xy":

Now we can write the simplified expression by combining the like terms:

So, the simplified expression is
.