Answer:
It is too hard to find out
A. Individual productivity is necessary for group productivity.
NOT:
<span>B. Waste isn't a problem in reaching group goals.C. Sacrifice isn't necessary to achieve group goals.
D. Individual productivity is more important than group productivity</span><span>
</span>
Completely unrelated, but that is a great sentence, I want that painted as a quote on my wall.
Also, the punctiation seems right to me. But you might be able to use a ";" instead of a comma, im gonna check that real quick.