This question asks which statement is NOT true. Options A, B, and D are all true statements about mutual funds - they ARE owned by all investors, they DO provide diversified portfolios, and they DON'T invest in real estate (they invest in securities). Option C claims investor objectives are diverse, which is FALSE - mutual funds are designed for investors with SIMILAR objectives (growth, income, etc.) as stated in the scheme's mandate. Therefore, C correctly identifies the statement that is 'not true'.