Correct answer - "24" : One read capacity unit represents two eventually consistent reads per second, for an item up to 4 KB in size. So that means that for an item of 12KB in size, we need 3 RCU (12 KB / 4 KB) for two eventually consistent reads per second. As we need 16 eventually consistent reads per second, we need 3 * (16 / 2) = 24 RCU.