Question

read the sentence.
on days when i go jogging in the morning, my mind seems to process ideas faster, and my mood is more positive.
how does the underlined clause add variety and meaning to the sentence?
it explains why jogging is beneficial.
it makes readers want to go jogging.
it creates a compound - complex sentence.
it adds detail about the speakers personality.

Explanation:

The underlined clause "On days when I go jogging in the morning" is an adverbial clause of time. It provides the context (the time when the main events in the sentence happen). Without this clause, the sentence would just be a general statement. With it, it adds a specific situation (the days when jogging occurs) which gives more details about when the speaker's mind processes ideas faster and mood is more positive. It's not creating a compound - complex sentence (a compound - complex sentence has at least two independent clauses and one dependent clause, and here we have one independent clause "my mind seems to process ideas faster, and my mood is more positive" and one dependent clause). It doesn't explain why jogging is beneficial (that would be a clause like "because jogging increases blood flow to the brain"). And it's not directly making readers want to go jogging (that would be more of a persuasive or motivational statement within the clause).

Answer:

It adds detail about the situation (time) when the main effects (mind processing ideas faster, mood more positive) occur.