La reacción de la amiga es estoy cansado
the answer is A. Imperfecto progresivo.
The progressive imperfect is used to express something that was taking place in the past. It is formed using the verb to be in past (in this case: estaba) plus the verb ending in ing (ando, endo, in this case: cantando). It is mainly used for: on-going actions that were happening in the past.
San Diego está en California.
Mi familia y yo somos de Perú.
Marta es de Brasil. Ella es Brasileña.
Ricardo no está feliz. Está triste.
Yo siempre estoy cansada.
