Question

drag the missing word into place
she needs a lot of
water.
to move those heavy buckets of
energy
matter
molecules

Explanation:

The sentence is about the requirement to move heavy buckets. "Energy" is the ability to do work, which fits the context of moving heavy objects. "Matter" refers to physical substance, and "molecules" are the smallest units of a substance. Neither "matter" nor "molecules" make sense in the context of needing something to move the buckets.

Answer:

energy