For those fluent in Spanish, please help me with these.

B, D, D, D, A

Explanation:

Spanish can be a difficult language to conjugate, so just keep in mind that if the noun is plural, then the possessive must be plural as well.

11. B. Su, because 'su' is the possessive noun for theirs, and they are talking about 1 dog, not 2, so it won't be plural.

12. D. Tengo, because tengo is the 'yo' form of tener.

13. D. Quince, because a quinceanera is a celebration for the 15th birthday, and quince is 15 in Spanish.

14. D. Su, because it is her birthday, and although it may seem like it should be 'sus' because cumpleanos ends with an s and seems plural, it can be both plural and singular, but because the sentence starts with 'Es', we can tell it is singular.

15. A. Hermanastra, because a madrastra is a stepmother, so her daughter would be your stepsister, or hermanastra.

Hope this helps :)