(a) 2 only
Champaran Satyagraha was associated with Mahatma Gandhi, not Vallabhai Patel.
Ahmedabad Mill Workers' Satyagraha was associated with Mahatma Gandhi, Vallabhbhai Patel, and Morarji Desai.
Maeda Satyagraha was associated with Rajendra Prasad, not Vallabhai Patel.
So, the correctly matched pairs are:
Movement/Satyagraha: Person Actively Associated with
Champaran: Mahatma Gandhi
Ahmedabad Mill Workers: Mahatma Gandhi, Vallabhbhai Patel, and Morarji Desai
Maeda: Rajendra Prasad
Therefore, the answer to the question is (b) 2 only.