These sentences can be complete in the following way:
1) Nadie.- this would mean that you do not know anyone.
2) Ningún- it makes reference to the book. you do not have a book
3) nunca. This means that you do not do that activity. you never do it
4) ni. not having one thing nor the other.
5) nada. this means that the table is empty- nothing on it.
Carolina: Mi amigo Ramón __es__ de Guatemala y ahora __está__trabajando en los Estados Unidos.
Option C
A Álvaro Le duelen las piernas. le
The professor doesn’t have any specific genders.
