Answer:
A. after, then
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.
Cause and effect can be defined as the relationship between two things or events in which an occurrence one (cause) leads to the occurrence of another (effect).
The key words or phrases which are used to show that a text is organized in a cause and effect pattern are "after, then."
For example, after drinking too much alcohol from the fridge, John couldn't walk and then was subconsciously forced to sleep by the fridge.
