Thesis: the benefits of exploring space justify the high cost.

counter-argument: the money spent on exploring space would do more good people here on earth.

which of these is the best response to this counter-argument?
a. we don't spend money wisely when we people on earth, so let's use that money for space instead.
b. we already spend enough money people here on earth
c. if we explore space, we'll learn more about science and be better able to people here on earth.
d. people would rather invest money in something that will guarantee huge returns, such as space exploration.