Peter Has Finished Subdividing the Product Groups in One of His

Multiple Choice

Peter has finished subdividing the product groups in one of his Shopping campaign's ad groups. What bid should Peter not use for the remaining "everything else in all products" product group?

A) A bid of zero
B) A bid lower than the subdivisions
C) A bid that's the average of the subdivisions
D) Continue subdividing until there are no products in this group