Cells C₁, C₂, and C₃ contain the values 2, 4, 6. If cells C₁, C₂, and C₃ were selected, and autofill used to fill C₄, C₅, and C₆, what would be the autofilled values?
a. 6, 6, 6
b. 8, 8, 8
c. 7, 8, 9
d. 8, 10, 12