Answer:
B. Perform experiments to test your hypothesis
Step-by-step explanation:
Scientific experiments involves using scientific method, which is an outlined manner of conducting an experiment. The scientific method consists of series of steps starting from making observation, followed by formulating an hypothesis, and then carrying out the experiments (as stated in the question).
According to this question, an observation that that three friends who were born in the same week like horror movies has been made. Using the scientific method, this was followed by formulating an hypothesis that "people born in that week like horror movies more than other genres of movies". Hence, this hypothesis will be tested out next by conducting an experiment.
The experiment will prove/disprove the hypothesis (a testable explanation). A way to carry out the experiment is by finding out if other people born in the same week as your friends like horror movies.