Answer:
The correct answer would be "está yendo"
Step-by-step explanation:
But, how is it the correct answer?
Simple, translate the sentence to English
Rafaela ________ (go) to the waterfalls today.
The options in English would be Is going, Are going ,Was going you, and were gone. Is going is the one that would make the most sense, in this case.
And, in Spanish it would make sense as well.
Rafaela está yendo a las cascadas hoy.
Hope this helps