The electrons of an atom:
a. are found in the nucleus along with the protons.
b. occupy the space surrounding the nucleus.
c. have a positive charge.
d. are attached to the positive charge of neutrons.

are found in the nucleus along with the protons.

Explanation:

i think it would be b. tissue because an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.

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