1. The answer to the question would be that the following ones are defining characteristics of language: Arbitrary and systematic (A and D). It is arbitrary because there is no fixed association between the words in a language and the objects or ideas it signifies or represents. What is more, language is systematic because it is rule governed: It consists of rules and conventions that regulate the structure, pronounciation and other words.
2. The answer to this question is that the statements that are not true are the following ones: English is a superior language and language definitions may vary. There isn't a superior language, English is considered a "universal" language because a lot of people speak it, wherever you go you are to find someone that speaks English but it is not a superior language.
Furthermore, language definitions do not vary. Language is the same in all cultures, it is a verbal means of communication.
