Concept of conservation refers to taking into account:

All profit
Only cash profit
Only profit realized
Profit realized and all possible losses

The correct answer is: D. Profit realized and all possible losses.

The concept of conservation refers to taking into account all potential losses and profits when making a decision. This means that you should not only consider the profit that you have already realized, but also the potential losses that you could incur. For example, if you are considering investing in a new business, you should not only consider the potential profits that you could make, but also the potential losses that you could incur if the business fails.

Option A is incorrect because it only considers profit. Option B is incorrect because it only considers cash profit. Option C is incorrect because it only considers profit realized.

I hope this helps! Let me know if you have any other questions.