Which of the the following is not the source of funds profit after taxshare capital issuedsale of investmentsshare buyback?

The source of funds typically refers to the means by which a company raises capital. Among the options provided, "share buyback" is not a source of funds; rather, it represents a use of funds as the company repurchases its own shares. In contrast, profit after tax, share capital issued, and sales of investments are all ways through which a company can generate or raise funds.