Question

La revista Cosas es mi favorita. ____________ todos los meses.

Answer 1

Leo would be the one like how she said ^

Answer 2

I'm pretty sure you would put "Leo" in the blank space because the verb "leer" means to read and the sentence prior to the blank space says "the magazine 'Cosas (or Things)' is my favorite. I read it every month.  Hope this helps!