You are given three grids, where each of them is 5 by 5 in size.
Grids have empty cells marked with "▢" and filled cells marked with "X".
You are also given a referring expression that describes one of the given grids.
Your task is to select the grid that matches the given referring expression.
Generate only the number (in text) of the grid that matches the given expression by selecting first, second, or third.

First:

X X X X X
X X X X X
▢ ▢ X ▢ ▢
X X X X X
X X X X X

Second:

X X ▢ X X
X X ▢ X X
▢ ▢ ▢ ▢ ▢
X X ▢ X X
X X ▢ X X

Third:

X X ▢ X X
X X ▢ X X
X X X X X
X X ▢ X X
X X ▢ X X

Expression: The target grid has a distinctive pattern of filled cells, with a central row of five filled cells surrounded by rows of four filled cells on either side. This pattern is not present in either of the distractor grids, which have different arrangements of filled and empty cells.
Question: Which grid does the expression refer to?
Start with the tag "Answer: ", followed by your selection. Omit any other text.

Answer: third
assistant
Answer: third
assistant