In which year is the proportion of copper production in the total mineral and metal production the highest?

The year wise total production of minerals and metals is as shown below:-
2005 = 69+91+71+15+100 = 346
2006 = 75+88+75+18+120 = 376
2007 = 81+97+79+21+102 = 380
2008 = 98+107+88+25+131 = 449
2009 = 93+110+92+24+143 = 462
2010 = 99+116+97+20+154 = 486
2011 = 105+122+103+125+103 = 215
Thus, the proportion of Copper in 2007 = $$\dfrac{79}{360} > 20\%$$
The proportion of Copper in 2008 = $$\dfrac{88}{449} < 20\%$$
The proportion of Copper in 2009 = $$\dfrac{92}{462} < 20\%$$
The proportion of Copper in 2010 = $$\dfrac{97}{486} < 20\%$$
Thus, as we can see the proportion of Copper in 2007 is the highest.
Hence, option A is the correct answer.