Answer:
A- Job
C- Ethnic
Step-by-step explanation:
Job - Speaking another language can be helpful for any job, for instance, you could be trying to help a customer/person out with something and they could speak another language, and not understand the one you already speak. In that situation, not only are you helping them out, you're practicing and showing your skills in that language, making your job that much easier.
Ethnic- The definition of Ethnic is: belonging to a population group or subgroup made up of people who share a common cultural background or descent. So if you are part of that group/population, they could speak whatever cultural language they are part of, and you wouldn't be able to understand if you don't know. Learning the language of your culture can be nice when talking to people of the same culture, that might not speak your language.
Hope this Helps!!! :)