the person who
Él es la persona a la que le di mi diccionario.
He is the person to whom I gave my dictionary.
La persona a la que llama está fuera del alcance.
The person you are calling is out of range.
— Guardianes Del Día (2006)
La persona a la que tratamos de atrapar es muy peligrosa.
The person we're trying to catch is very dangerous.