The correct answer to this open question is the following.
Unfortunately, you did not include the options for this question or further context and reference. However, we can help with the following general comments.
Many people fail to balance their budget because they do not know how to establish priorities or they do not respect the priorities established at the beginning of the month. That is why is too important to be financially disciplined and only spend money on what is needed, instead of fall in the temptation of buying things that are not needed and were not considered priorities. If this happens, at the end of the month you will have a deficit and no money down to finish the month.