I'm going to agree its a young adult deer, as the deer gets older (4-5 years) the molars will start showing signs of wearing down in height and the small front will wear down flush with the gun line and some even fall out.
The molars are still very high in that pic and it has all the smaller front teeth intact and in good shape.
definatlay not older than 3.My taxidermist was showing me the chart on how to read the teeth and there was hardly any diffrence between 2 and 3.He said that even he has trouble judging it sometimes.