Depending on Who You Ask, You Will Get Different Answers

Depending on who you ask, you will get different answers regarding how to distinguish a pull system from a push system depending.Choose the likely bases for distinguishing a pull system from a push system depending.
1) Information flow
2) Order release
3) Shop floor WIP levels
4) Lot size

A) (1)
B) (2) and (4)
C) (1) , (2) and (3)
D) (4)