The correct answer is option 3, Ahmedabad. This struggle, based on Gandhi`s philosophy of Satyagraha, involved the industrial working class. Satyagraha can be defined as a nonviolent form of resistance or civil disobedience, and it was a major aspect of Gandhi`s leadership during the Indian independence movement.

Now let`s evaluate the other options:

Option 1, Champaran: The Champaran struggle was a movement led by Gandhi in Bihar, India, to alleviate the problems faced by the indigo farmers. This struggle did not specifically involve the industrial working class.

Option 2, Kheda: The Kheda struggle was a movement led by Gandhi in Gujarat, India, to protest against the high taxation imposed by the British on the farmers. This struggle also did not specifically involve the industrial working class.

Option 4, Bardoli: The Bardoli struggle, also led by Gandhi, was a movement in Gujarat, India, to protest against the increased land revenue by the British government. Again, this struggle did not specifically involve the industrial working class.

In conclusion, option 3, Ahmedabad, is the correct answer as it specifically refers to a struggle that involved the industrial working class based on Gandhi`s philosophy of Satyagraha.