Respuesta :
Answer:
A. Flashcards.
Explanation:
This has been in use since the 19th century, just as the name sounds, so does is directly apply to its explanation as a card which is seen to bear conceptual informative facts used in memorization; it could be in a course of teaching to someone or a group of people and also applies to someone learning by him/herself. It has been a tool in the modern form of impacting in such a way that it now moves from cards that contains information in its front and back to having seen to be tools in online format to aid quick learnjng and mastering of certain notes.
