Which of the following cannot be considered a mutagen?

Gene mutation is caused by

Haploids are more useful than diploids for the study of mutations because...

The process of genetic mutation is

Replacement of which one of the following nucleotides in the $Hb^A$ gene causes sickle cell anaemia?

The chromosome shown in the diagram below is broken at the points which are indicated by the arrows and the genes between these points become inverted. The resulting order of the genes will be: