Answer/Explanation:
Sexual reproduction is a a combination of chromosomes from each mate. Since each mate has different pairs, when combined they produce a completely different product.
This product has half of the characteristics from both sides.
Below is an example of how this works. The bold cells are from one mate and the other is from the other.
X ---> >< <--- X
X ---> >< <--- X
X ---> >< <--- X
X ---> >< <--- X
X ---> >< <--- X
As shown, the cells broke in half and combined with the other half forming a cell of 50/50. With this process it never created an identical offspring but different ones each time since different parts of the cell combines in different ways but still remains half of one and half of the other.