Hiii, uh. .. help?

so basically you have to fill in a single letter in the blanks. for example, where it says gra_ias you would put a c in the blank to make it read gracias. and so on, so if you look at the words think of some other spanish words that look like it, and figure out what letter is missing.

The answer is b because it’s los amigos . los amigos is plural and dicen is plural and masculine .