Answer:
D texture of the jumping surface
Explanation:
An experiment can be defined as an investigation which typically involves the process of manipulating an independent variable (the cause) in order to be able to determine or measure the dependent variable (the effect).
This ultimately implies that, an experiment can be used by scientists to show or demonstrate how a condition causes or gives rise to another i.e cause and effect, influence, behavior, etc in a sample.
A control experiment can be defined as an experiment in which a condition assumed to be a probable cause of the effect is being compared to the same situation by the scientist without involving or using the suspected condition.
In an experiment , the variable being manipulated by an experimenter is known as an independent variable while the dependent variable is the event expected to change when the independent variable is manipulated.
Furthermore, a controlled variable refers to anything or quantity such as group, person, event, etc., that is held constant by the researcher during an experiment and as such is limited.
In this scenario, you are designing an experiment to find out which type of frog can jump farther. Thus, the controlled variable (variable that does not change) in this experiment is the texture of the jumping surface because it is where all the frogs would be tested on i.e used for the jumping test.
They allied with settled neighbors to repel common enemies.
