Choice "C" is correct. The elimination of the tables line will eliminate unavoidable costs to the extent that they do not produce an operating loss. The rental income net of the reduced costs is the amount by which operating income will increase computed as follows:

Viewed as a comparison, the change in operating income is as follows:

Choice "d" is incorrect. The net income in this answer does not consider the operating loss incurred as part of the table line. The difference, 13,200 (24,000 - 10,800), understates income. Choice "a" is incorrect. The increase in net income is not the total amount of rental income.Choice "b" is incorrect. The increase in net income is not the amount of rental income plus the eliminated operating loss before adjusting for unavoidable costs.