Zakatul-fitr is a compulsory charitable donation that Muslims give at the end of Ramadan. The donation is meant to provide food for those in need during the festival of Eid al-Fitr.
In terms of the options provided, it is important to note that Zakatul-fitr cannot be given in the form of kolanut, as kolanut is not considered a food staple in most Muslim communities.
On the other hand, rice, maize, and millet are all acceptable forms of Zakatul-fitr as they are considered food staples in many Muslim communities. However, it is important to ensure that the chosen food staple is something that is commonly eaten in the community and is readily available to those in need.