Which of the following represents the functional group of an ether?

The functional group of an ether is represented by the structure C-O-C. This structure features a central oxygen atom that is bonded to two carbon-containing groups (R), specifically represented as R-O-R'. In an ether, the oxygen atom connects two alkyl or aryl groups, which distinguishes it from other functional groups like alcohols or phenols, where the hydroxyl (-OH) group is bonded to a carbon atom.

In the context of the other options:

• C6H5 represents a phenyl group, which is part of aromatic compounds, and does not indicate any oxygen bond.

• R-SH is the functional group of a thiol, characterized by a sulfur atom bonded to hydrogen and an organic group, which does not involve oxygen.

• PO4^3- denotes the phosphate group, commonly found in nucleotides and ATP, and while it involves oxygen, it functions differently in biochemistry.

Thus, C-O-C clearly identifies the ether functional group, distinguishing it based on its specific structure and bonding arrangement.