Explanation:

• Option A (Incorrect): In a price-weighted index, the weight of each constituent security is determined by dividing its price by the sum of all constituent prices. Therefore, changes in free float (e.g., due to increased shares held by controlling shareholders) do not affect the constituent weights.

• Option B (Incorrect): An equal-weighted index assigns the same weight to each constituent security at inception. Thus, variations in free float (e.g., due to higher shares held by controlling shareholders) do not influence the constituent weights.

• Option C (Correct): A float-adjusted market-capitalization-weighted index accounts for shares available for public trading by excluding those held by controlling shareholders. The constituent weights are based on the float-adjusted market capitalization (market price per share multiplied by the number of publicly available shares), making them sensitive to changes in free float.