Final answer:
Amgen's phrase 'To serve patients' is correctly identified as the company's motto, which serves as a brief and impactful statement reflecting its mission and guiding principles.
Step-by-step explanation:
Amgen's motto, "To serve patients," may be one of the world's shortest. This statement is a reflection of the company's dedication to its mission and its guiding principles which is succinctly encapsulated in its motto. A motto is a brief phrase that captures the essence of an entity's values, ideals, or mission, often used to inspire and guide the conduct of its members. Slogans, logos, and anthems can also be reflective of a company's ethos, but in this case, the motto is the correct term for Amgen's phrase "To serve patients".