To test the quality of water sources in her area, Shameka collects five samples from each water source and tests the quality of each sample.

The missing part of the incomplete question is given below:

Which important step of scientific design is Shameka conducting?

repetition

replication

verification of results

using controlled variables

Verification of results

Explanation:

The way toward gathering five examples of water from various sources is conveyed to confirm the outcome. By gathering water from five distinct areas of a similar source the analyst can genuinely find out the nature of the water in her region of remain.  

On the off chance that after examples are tried it is found the water isn't sound, the outcomes would be acknowledged as it has been appropriately checked and a  proper move would be made.

Thus, the correct answer is - verification of results

they start with the same

.) the observation by semmelweis that more mothers died of childbed fever when their doctors also worked in the morgue