There may be an easier way but 2 queries
SELECT tblProduct.Group, Min(IIf([Product]="HMO",IIf([Product]="PMO","Both",[Product]),[Product])) AS Test, Max(IIf([Product]="HMO",IIf([Product]="PMO","Both",[Product]),[Product])) AS Test2
FROM tblProduct
GROUP BY tblProduct.Group;
and the second...