Which one of the following movements has contributed to a split in the Indian National Congress resulting in the emergence of 'moderates' and 'extremists'?

1. A

   Swadeshi Movement

   The Swadeshi Movement after the 1905 Partition of Bengal deepened the moderate–extremist rift, which surfaced at the Surat session of 1907. That split produced the two camps named in the question. This option is the official key.

2. B

   Quit India Movement

   The Quit India Movement of 1942 came long after the 1907 split; Congress was not then dividing into Moderates and Extremists. This option is not the key.

3. C

   Non-Cooperation Movement

   Non-Cooperation (1920–22) is a Gandhian mass movement after the Extremists had already been a distinct group. It did not create that split. This option is therefore wrong.

4. D

   Civil Disobedience Movement

   Civil Disobedience (1930 onwards) is likewise far later than Surat 1907. This option is not the key.

Summary. Official key is (a) Swadeshi Movement. The 1905–08 Swadeshi upsurge, methods of boycott versus constitutionalism, and the Surat split of 1907 created the Moderate and Extremist wings. Quit India, Non-Cooperation and Civil Disobedience belong to a later Gandhian phase. Dating alone rules out (b), (c) and (d). Only Swadeshi fits the emergence of those labels.