In 1916 Mahatma Gandhi travelled to which region in India to inspire peasants to struggle against the oppressive indigo plantation system?

Introduction / Context:
Mahatma Gandhi experimented with different forms of satyagraha after his return to India. One of his earliest major interventions involved the plight of peasants forced to grow indigo under oppressive conditions. Understanding where these early experiments took place is vital for Indian national movement history. This question tests knowledge of the region Gandhi visited in 1916 in connection with the indigo plantation system.

Given Data / Assumptions:
- The year mentioned is 1916, early in Gandhis Indian phase.
- The struggle is against an oppressive plantation system based on indigo cultivation.
- The options name places like Dandi, Sabarmati, Champaran, Chauri Chaura, and Kheda.

Concept / Approach:
The Champaran movement is famous as Gandhis first satyagraha in India, aimed at the grievances of indigo cultivators in Bihar. Other places in the options are associated with different events, such as the Dandi March or the Kheda satyagraha. The correct method is to recall the association between Champaran and the indigo issue and match the date 1916 with this event.

Step-by-Step Solution:
Step 1: Recall that Gandhi returned to India in 1915 and soon took up local issues to learn about the country.
Step 2: Remember that Champaran in Bihar was known for the tinkathia system, where peasants had to grow indigo on a fixed portion of their land for European planters.
Step 3: In 1916 Gandhi was invited by local leaders to Champaran to study and support the peasants struggle, which led to an important satyagraha.
Step 4: Confirm that Dandi is linked with the 1930 Salt March, Kheda with a later peasant satyagraha, and Chauri Chaura with a violent incident in 1922, not with the 1916 indigo issue.
Step 5: Therefore Champaran in Bihar is the correct answer.

Verification / Alternative check:
A simple alternative check is to link events with keywords: Champaran with indigo, Kheda with tax relief for peasants, Dandi with salt, and Chauri Chaura with the withdrawal of the Non Cooperation Movement. Only Champaran fits the description of the 1916 struggle against the plantation system based on indigo.

Why Other Options Are Wrong:
Option a is wrong because Dandi is famous for the 1930 Salt March, not for an indigo plantation struggle.
Option b is wrong as Sabarmati is associated with Gandhis ashram near Ahmedabad rather than this specific peasant movement.
Option d is wrong since Chauri Chaura refers to the 1922 incident in which a violent clash led Gandhi to call off the Non Cooperation Movement.
Option e is wrong because Kheda in Gujarat is connected with a later satyagraha over land revenue, not with indigo plantations in 1916.

Common Pitfalls:
Students sometimes mix up Gandhis various mass movements and associate any peasant issue with Kheda or any rural protest with Chauri Chaura. Another frequent error is to treat Dandi as a general symbol of all satyagrahas. Maintaining a chronological list of key movements helps keep the associations clear.

Final Answer:
In 1916 Gandhi travelled to Champaran in Bihar to support peasants against the oppressive indigo plantation system.