DotBomb, Inc. runs an online retail business through its website, DotBomb.com. In addition to its own sales of a wide range of retail products, DotBomb sells advertising space on its site. It does so through a team of in-house sales people, whom advertisers contact by calling a number on the "Contact Us" page of the website. Often enough, though, DotBomb's sales people make cold calls to potential advertisers, which they can follow up w/ marketing materials including their business cards and correspondence on company letterhead.

When DotBomb salespeople make cold calls that result in contracts for the sale of advertising space, the contracts are enforceable because:

(A) The salespeople have actual authority, assuming the contracts are for less than 6 months.
(B) The salespeople have apparent authority by virtue of the business cards and other materials they can distribute.
(C) The salespeople have apparent authority if it is customary in the industry for contracts of this nature to be sold by salespeople w/o prior approval.
(D) a and b are both correct.
(E) a, b, and c are all correct.