The melodies of Assamese folk songs can be described as:

The correct answer is: d) Varying across different genres.

Assamese folk songs are a diverse and vibrant tradition, with a wide range of melodies and styles. Some Assamese folk songs are simple and repetitive, while others are complex and ornamental. Some Assamese folk songs are influenced by Western music, while others are purely traditional. The melodies of Assamese folk songs vary across different genres, reflecting the unique cultural and historical influences of each genre.

Here is a brief description of each option:

• a) Simple and repetitive. Some Assamese folk songs are simple and repetitive, with a clear melody that is easy to sing along to. These songs are often used for dancing or other communal activities.
• b) Complex and ornamental. Other Assamese folk songs are more complex and ornamental, with intricate melodies and rhythms. These songs are often used for more formal occasions, such as weddings or religious ceremonies.
• c) Influenced by Western music. Some Assamese folk songs have been influenced by Western music, particularly in the use of instruments and harmonies. These songs are often performed by younger people who are interested in fusing traditional Assamese music with contemporary styles.
• d) Varying across different genres. The melodies of Assamese folk songs vary across different genres, reflecting the unique cultural and historical influences of each genre. For example, the melodies of Bihu songs are often lively and energetic, while the melodies of Bhatiali songs are more somber and reflective.