Hey Student!
So, the hypothetical part ' present self cannot be the future version of themselves.
I don't know what part is confusing me.
It is a tricky concept to grasp; think about it this way: the hypothetical situation is similar to a person thinking about himself in the future (he thinks of his future self as he would another person). This is why the graph shows similar lines for the future self and hypothetical situation. Don't worry if you still aren't 100% certain =).
To your second question: your thought was very good! The problem with D) is that it mentions "from one year to the next". However, the graph does NOT show evidence for changes in time. So you would be speculating too much with answer D). However, answer B) is directly supported by the graph since the graph shows evidence that Peak frequency is "correlated with body mass". This is a much more direct and clear answer. Good reasoning skills! =)
Keep working on your process! You got this!
Keep Moving Forward!