implementation shortfall components

Which of the following measures cannot be used to analyse implementation shortfall?

Explicit trading costs.

_ Realized profits/losses due to price changes for trades taking one day to complete. _

Slippage costs.

B is the answer but not able to understand why because B is representing market or price impact which is a component of implicit cost in implementation shortfall.

thanks in anticipation

Someone will surely answer this correctly, but my guess is maybe if the trade takes one day to complete and there is no Cancelation price, you can’t totally calculate Realized P/L? Just a guess, again wait for someone to hopefully give the right answer.