A Only one variable changed
Hydrologists are most likely to perform actions relating to estimating the amount of groundwater in an aquifer.
<h3>Hydrologists</h3>
Hydrologists are scientists that specialize in the study of how water relates to the various crusts of the earth.
Hydrology in itself refers to the branch of science that studies how water moves relative to the earth's crusts.
Thus, species identification, age of fossils, or extracting underground oils have nothing to do with the work of hydrologists.
More on hydrology can be found here: brainly.com/question/13554728
The correct answer is that variable number repeats are used in DNA tests; they have hundreds of possible lengths. Eye color is determined by variations in a person's genes. Most of the genes associated with eye color are involved in the production, transport, or storage of a pigment called, melanin. Eye color is directly related to the amount and quality of melanin in the front layers of the iris.
