Evaluate$2$exxdx.$2$exxdx.

Select one:

a$.$

$2$xex$2$ex$2$xex$2$ex

b$.$

$2$xex$+2$ex$+$c$2$xex$+2$ex$+$c

c$.$

$2$xex$2$ex$+$c$2$xex$2$ex$+$c

d$.$

$2$xex$+2$ex