There’s nothing inherently wrong in investments of any form as long as there’s no aspect of immorality or polytheism involved.
As for Mutual Funds/Index Funds, your preference should be that you pick the ones that don’t make investments in Haram businesses. And if there is no such choice available, then atleast one should choose those funds where significant portion of their investments are made in Halal businesses and its best that proprotion of income of fund earned through investement in a bank be given in charity.
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Discussion 80330