An index fund is planning to track Dow-30. It investes 1/30th on the portfolio in each of the Dow 30 stocks. Will the index fund track Dow accurately ? Cheers 
No, the Dow is price weighted so an equally weighted portfolio will not (perfectly) mimic the Dow’s performance.
yeah go ahead and put 1/30th into C
with all respect, there is a special block after each chapter exactly for this kind of questions please stop garbaging the forum
Using naive diversification, no.