Four words have been given, out of which three are alike in some manner and one is different. Select the word that is different.

Geology

Geology - The science which deals with the physical structure and substance of the earth,and their history

Entomology -the scientific study of insects

Mycology - the branch of zoology concerned with the scientific study of fungi

Genomics - the branch of molecular biology concerned with structure ,evolution and mapping of genomes