Let the 4 cells in the fourth (last) row from left to right be denoted as c1,c2,c3,c4.
We are given that no cell in the fourth row contains a cross (X). Therefore, all neighbors within row 4 do not have crosses.
Let us calculate the count of immediate non-cross neighbors for each cell in row 4:
Cell c1 (row 4, column 1):
Neighboring cells: (3,1), (3,2), and (4,2). (Total = 3 neighbors)
Non-cross neighbors: (3,1) which is 3, and (4,2) which is a number.
Cross neighbor: (3,2) which is X.
Value of c1=2.
Cell c2 (row 4, column 2):
Neighboring cells: (3,1), (3,2), (3,3), (4,1), and (4,3). (Total = 5 neighbors)
Non-cross neighbors: (3,1), (3,3), (4,1), and (4,3).
Cross neighbor: (3,2) which is X.
Value of c2=5−1=4.
Cell c3 (row 4, column 3):
Neighboring cells: (3,2), (3,3), (3,4), (4,2), and (4,4). (Total = 5 neighbors)
Non-cross neighbors: (3,3), (4,2), and (4,4).
Cross neighbors: (3,2) which is X, and (3,4) which is X.
Value of c3=5−2=3.
Cell c4 (row 4, column 4):
Neighboring cells: (3,3), (3,4), and (4,3). (Total = 3 neighbors)
Non-cross neighbors: (3,3) and (4,3).
Cross neighbor: (3,4) which is X.
Value of c4=3−1=2.
Sum of the four numbers filled in the last row:
Sum=c1+c2+c3+c4=2+4+3+2=11 Thus, option (A) is correct.