The economic concept of efficiency a. is the same as productivity, or the number of units of output per unit of input.
b. has a static (point-in-time) dimension as well as a dynamic (leading to the best possible future) dimension.
c. is not consistent with the "economic way of thinking" of optimization
d. applies only to optimization at the individual person or firm level.
e. is proposed as one of the value standards by which policies, actions, decisions can be judged good or bad, just as people use the idea of fairness or justice as standard to make such judgments.
f. in its most general meaning has philosophical antecedents in the utilitarian concept of "the greatest good for greatest number"
g. is always understood in a purely materialistic context.
h. is limited to a "point-in-time" static view.