The correct answer is: a) June-July to October-November.
The Sali rice crop is a short-duration rice variety that is grown in the Brahmaputra valley of Assam. It is sown in the monsoon season, from June to July, and harvested in the autumn, from October to November. The Sali rice crop is a major source of food for the people of Assam. It is also an important cash crop, and is exported to other parts of India and the world.
The other options are incorrect because they do not correspond to the actual sowing and harvesting periods of the Sali rice crop. Option b) is incorrect because the Sali rice crop is not sown in the winter months of December and January. Option c) is incorrect because the Sali rice crop is not harvested in the spring months of April and May. Option d) is incorrect because the Sali rice crop is not sown in the winter months of October and November and is not harvested in the spring months of February and March.