The number of ether metamers represented by the formula $C_4H_{10}O $ is -
The formula $C_4H_{10}O$ can give rise to three ether metamers: 1. Diethyl ether (CH$_3$CH$_2$OCH$_2$CH$_3$), 2. Methyl propyl ether (CH$_3$OCH$_2$CH$_2$CH$_3$), and 3. Ethyl methyl ether (CH$_3$CH$_2$OCH$_3$). These are the three possible structures, hence the correct option is 3.