What is the rule for this number pattern?
1, 1, 2, 6, 24, 120, . . .
AAdd 0, then add 1, then add 2, and so on
BMultiply by 1, then multiply by 2, then multiply by 3, and so on
CMultiply by 1, then add 1
DMultiply by two, then subtract 1
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.I mean its b