Whether Supplier-Seller Relationships in an Industry Represent a Strong or Weak

Whether supplier-seller relationships in an industry represent a strong or weak source of competitive pressure is a function of:

A) whether the profits of suppliers are relatively high or low.
B) the number of suppliers that each seller/industry member purchases from on average.
C) how aggressively rival industry members are trying to differentiate their products.
D) whether demand for supplier products is high and they are in short supply.
E) whether the prices of the items being furnished by the suppliers are rising or falling.