The following items are available for use in a pan balance to measure the weight of a large rock. Which items will yield the greatest level of accuracy, that is, approximate the true weight of the roc

The following items are available for use in a pan balance to measure the weight of a large rock. Which items will yield the greatest level of accuracy, that is, approximate the true weight of the rock with the least error? You may only use items of the kind selected, and may not mix items.

A. marbles

B. salt

C. basketballs

D. oranges