Explanation:

One of the problems in an IPO has been the post-issue price decline as compared to the issue price. This often has left retail investors feeling high and dry. A solution to this problem is the introduction of the 'Green Shoe' Option in the issue. The first company to use this innovative structure was the 'Green Shoe Company' and hence, the unique name. Under a 'Green shoe' option, the issuing company has the option to allocate additional equity shares up to a specified amount. A 'Green shoe' option allows the underwriter of a public offer to sell additional shares to the public if the demand is high. The option is a clause in the underwriting agreement, which allows the company to sell additional shares, usually 15 per cent of the issue size (in case of IPO), to the public if the demand exceeds expectations and the stock trades above its offer price. Hence option (d) is correct.