Answer:
1. C
2. A
3. B
Explanation:
1- Ser is an infinitive, meaning it's not conjugated.
2- The question asks how old you are, so answering with tener conjugated in the "yo" form (tengo) is the only way to answer in a way that makes sense.
3- Bandera=flag, you wouldn't add an s to verde because there is only one flag. Singular noun = singular adjective