Final answer:
The provider's name and address that are printed at the top of formal business stationery is called letterhead.
Step-by-step explanation:
The correct answer is b) Letterhead.
The provider's name and address that are printed at the top of formal business stationery is called letterhead. It typically includes the company name, logo, and contact information.
Letterhead is an essential component of professional correspondence and helps to establish a business's identity and credibility.