Answer:
IV- Their Diet DV- Blood Pressure
Step-by-step explanation:
You can always think of your IV as the variable that's gonna "change" and your DV will be "measured". So ask yourself what's being changed, and measured?
Well we can infer that blood pressure is what the researcher is measuring. We know this because his whole goal in the experiment is to see a change.
And IV we can infer will be what's changing. I believe their diet would be what's changing.
I hope this helps! Try and use the replacement words for the IV and DV, they help a lot!!
Thanks for letting me help!!