What Is the Fundamental Difference Between Profit-Sharing and Gainsharing

What is the fundamental difference between profit-sharing and gainsharing?

A) Profit-sharing rewards employees based on the profit the company earns,while gainsharing rewards employees based on productivity improvements.
B) Profit-sharing has been shown to be more motivating for employees than gainsharing.
C) Profit-sharing allows more specific measurement of improvements than gainsharing.
D) Profit-sharing focuses on group rewards,while gainsharing focuses on individual rewards.
E) Profit-sharing is used mostly by large companies,while gainsharing is used mostly by small companies.