That ethanol (a monohydric alcohol) and methanol have polyhydric analogues (such as ethylene glycol and glycerol) is a fundamental chemical fact and common knowledge, so no citation is needed.
The claim states that ethanol and methanol have analogues with more than one hydroxyl group. Methanol (one carbon, one hydroxyl) and ethanol (two carbons, one hydroxyl) do indeed have well-known polyhydric analogues, such as ethylene glycol (a diol corresponding to the two-carbon chain of ethanol) and glycerol (a triol corresponding to a three-carbon chain, among others). This is a basic matter of organic chemistry nomenclature and classification, qualifying as common knowledge. Therefore, following the instructions, balance_verdict is set to COMMON_KNOWLEDGE with empty indices and notes.