The year in which the percentage increase in the profit from that of the previous year is the highest is

profit increased only in the years 2004, 2006, 2007, 2008, 2009 & 2010.

 percentage increase in the profit in 2004 = $$\frac{50-20}{20}\times100=\frac{30}{20}\times100=150$$%

 percentage increase in the profit in 2006 = $$\frac{50-40}{40}\times100=\frac{10}{40}\times100=25$$%

 percentage increase in the profit in 2007 = $$\frac{55-50}{50}\times100=\frac{5}{50}\times100=10$$%

 percentage increase in the profit in 2008 = $$\frac{70-55}{55}\times100=\frac{15}{55}\times100=27.27$$%

 percentage increase in the profit in 2009 = $$\frac{75-70}{70}\times100=\frac{5}{70}\times100=7.14$$%

percentage increase in the profit in 2010 = $$\frac{90-75}{75}\times100=\frac{15}{75}\times100=20$$%

so the answer is option D.