In the TAB staff, the highlighted part represents A. a fret
B. a string
C. a bar line
D. a double bar line

Thanks so much for helping
I will give brainliest to the most detailed answer!

Notes are placed on or in-between these lines to represent notes on the guitar.

The staff is split up into bars (or measures) using vertical lines called bar lines:

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Music staff bar lines

The position of these bar lines depends on how many notes are in the bar and the time signature (covered later). Every bar lasts the same length of time unless a time signature tells you otherwise.

Explanation:

np

i think it's about 10 mins.

actually i think that's wrong, but i don't know how to delete this.

but who knows it might be right.