America should be accepted together with the other most common name, US (we could argue that America is confusing and can refer to the two Americas, but its usage to refer to USA is so widespread that it should be accepted)
Throughout the rest of the course, America is accepted for Marekani, so I think it's just an omission here. It should be "
the USA" or "
the US" though.
Also, in English, "America" virtually never refers to the Americas as a whole - a fact which seems to annoy a lot of Spanish speakers because that is the meaning of their word América. When we refer to both continents together, it's "
s" or individually "North America" and "South America" (as well as "Central America" as a part of North America).