Juan: ? tienes el libro de historia? ricardo: no, a mariana. a. la presté b. las presté c. lo presté d. los presté

The answer is C. I lent it (masculine) because there is only ONE history book (it) and it's "el libro", in masculine form.

Juan: Do you have the history book?

Ricardo: No, to Mariana.

A. I lent it (feminine) B. I lent them (feminine) C. I lent it (masculine) D. I lent them (masculine)

Juan: ?Tienes el libro de historia? Ricardo: No, a Mariana. A. La presté  C. Lo presté D. Los presté

B. Las presté

de estos colores. sounds about right.