Consider a cube defined on the following dimension hierarchies and then answer the three questions related to it: {customer < customer_city < customer_state} {supplier < supplier_city < supplier_state} {product < product_group}.
Which of the following is a valid cuboid in this cube? select all that apply___
a) (customer_state, supplier, supplier_state, product_group)
b) (customer_state)
c) (customer, supplier, product)
d) (customer_state, supplier, supplier_state)
e) (customer_state, supplier, product_group)
f) (product, product_group)