First we convert the tiles to expressions. Similar tiles can be summed up and written as one term. For example 2 tiles of x can be written as 2x.
So we are to add [tex] x^{2} +x[/tex] to [tex]2x+3[/tex].
The summation will be:
[tex] x^{2} +x+2x+3 \\ \\ = x^{2} +3x+3[/tex]
Therefore, option B is the correct answer.