Reap is the opposite of what obtain cheer continue exist or sow?

The opposite of "reap" is "sow." While "reap" refers to gathering or harvesting the results of something, often used in the context of collecting the fruits of one's labor, "sow" means to plant seeds or initiate a process. The other options—obtain, cheer, continue, and exist—do not directly relate to the act of planting or harvesting.