Who sells strike?

A strike is typically sold by an options trader or investor who believes that the underlying asset will not reach the strike price before the option's expiration. This process is known as writing or selling options, and it can be done by individual investors or institutions. The seller receives a premium from the buyer of the option, which is the income generated from the transaction. In this context, the seller takes on the obligation to fulfill the option contract if it is exercised by the buyer.