Answer: The correct answer is -
isomers.
Step-by-step explanation:
Isomers can be described as chemical compounds having same chemical formula but possess different structures, which show difference in the arrangement of atoms in the molecule.
Glucose and fructose are structural isomers as they both have same molecular formula that is C6H12O6 but there is difference in the arrangement of the atoms involved in them.
Refer the figure attached.
Thus, isomers is the right answer.