A common size income statement analysis would show what figure for the following company:

2020	2019
Net sales	$678,500	$630,485
Cost of goods sold	$195,000	$186,405
Gross margin	$483,500	$444,080
Selling/administrative costs	$115,000	$128,350
Operating income	$368,500	$315,730
Income tax expense	$73,700	$63,146
Net income	$294,800	$252,584

A. 2020 operating income (as a percent of net sales) is 54.3%

B. The change in gross margin is $39,420

C. The 2020 change in operating income is $52,770

D. The percent change in net income is 16.7%