The Assam movement, which began in the late 1970s, had both cultural and economic dimensions:
1. Cultural Pride: The movement was fueled by the desire to protect the Assamese language, culture, and identity against the influx of non-Assamese migrants, particularly from Bangladesh.
2. Economic Backwardness: Assam, despite being rich in resources, remained economically backward, with a lack of infrastructure and development. The people felt that the state's resources were being exploited without benefiting the local population.
3. Political and Economic Demands: The movement sought the expulsion of illegal immigrants and greater autonomy for the state, alongside development that would address the economic backwardness of the region.
Thus, the correct answer is (b).