Actually the correct answer is D. tendrá. Because A would be if you were talking about yourself. B would be if you were taking about a group including yourself, and C would be right if you were talking about a group not including yourself.
13. Tú repites
14. Ella compra
15. Nosotros ocurrimos
16. Yo ando
17. Ustedes beben
18. El deber
19. Usted llama
20. Ellas viven
21. Ellos creen
Amable would be the best answer because its a friendly gesture.
Well id have too see the blog post and the video too help out i'm fluent in spanish so id be able to help out :)
