Step 1: Read the question.
We must arrange four events in time order: Dandi March, Rowlatt Act, Simon Commission, and Morley-Minto Reforms.
Step 2: Note the year of each.
Morley-Minto Reforms were in 1909. The Rowlatt Act was in 1919. The Simon Commission came in 1928. The Dandi March was in 1930.
Step 3: Put them in order.
Earliest to latest: 1909 (d), then 1919 (b), then 1928 (c), then 1930 (a).
Step 4: Write the sequence.
The order is d, b, c, a.
Step 5: Match the option.
This matches the choice d, b, c, a.
Step 6: Conclude.
The correct chronological order is d, b, c, a.
Answer: d, b, c, a