The question asks about the language family to which the Indo-Aryan language group belongs. To answer this, we need to understand the classification of languages into various families based on their historical linguistic relationships.

The Indo-Aryan languages are a significant branch of the Indo-European language family. This family is one of the largest and most widespread language families in the world, which includes languages spoken in most of Europe, and eastern, western, and southern Asia.

Let's evaluate each of the given options:

1. Dravidian: The Dravidian language family is primarily spoken in southern India and includes languages such as Tamil, Telugu, Kannada, and Malayalam. It is unrelated to the Indo-Aryan group. Thus, this option is incorrect.
2. Austro-Asiatic: This language family includes languages spoken in Southeast Asia and parts of India, such as Khasi and Munda languages. It is not related to the Indo-Aryan language group. Therefore, this option is incorrect.
3. Indo-European: The Indo-European language family includes several major branches such as Germanic, Romance, Baltic, Slavic, Celtic, and Indo-Iranian. The Indo-Aryan languages are a subgroup of the Indo-Iranian branch. As such, this is the correct answer.
4. Sino-Tibetan: This family includes languages such as Chinese, Burmese, and Tibetan. It is not related to the Indo-Aryan languages. This option is also incorrect.

In conclusion, the Indo-Aryan language group belongs to the Indo-European family. Hence, the correct answer is \(Indo-European\).