Ans.
The modern humans (Homo sapiens) are grouped into genus Homo, which includes several other extinct species of ancestral species of modern humans, such as Homo erectus.
The first member of genus Homo was Homo erectus, which appeared in east Africa about 2.3 to 2.4 million years ago. Homo erectus is ancestral species of Homo sapiens, from which they evolved around 3.5 million years ago by the speciation.
Thus, the correct answer is genus 'Homo.'