it is actually depends on the Kind of Mutual fund
1) if Equity Oriented MF is sold - for Less than one year then 10% taxable & it is STCG if sold after one year of purchase then the same is full exempted u/s.10(38) & i.e. LTCG
2) if MF is Liquid fund - then the surplus amount what ever is recd. will be treated as Dividend fully exempted u/s.10(35)
3) if the MF is Fixed tem Plan (FMP) - then in this case there are two types of treatment one is Dividend (surplus recd. on redemption) is tax fee u/s.10(35) of another it will be treated as LTCG with indexation taxable @ 20% depending upon the type of fund - plan & options & period of investment.
i think this will clear your all queries....