The IUPAC name of the compound is:

The amine functional group takes precedence in numbering, so the carbon bearing the NH2 should have the lowest possible number. For a hexane chain with a methyl substituent and an amino group, numbering from the end closer to the amine gives the amino group at position 3 and the methyl at position 5, yielding 5-methyl-3-hexanamine. The alternative numbering (amino at 4, methyl at 2) results in higher locant for the principal group. The suffix '-amine' is preferred over 'amino-'. Therefore, option B is correct.