Complete the rows 0 through 6 of Pascal's Triangle:
Row 0: 1
Row 1: 1_ _ _ _ _ _ _
Row 2: 1_ _ _ _ _ _ _
Row 3: 1_ _ _ _ _ _ _
Row 4: 1_ _ _ _ _ _ _
Row 5: 1_ _ _ _ _ _ _
Row 6: 1_ _ _ _ _ _ _

A) 1, 1, 1, 1, 1, 1, 1
B) 1, 2, 1, 1, 2, 1, 1
C) 1, 3, 3, 1, 1, 3, 3
D) 1, 4, 6, 4, 1, 4, 6