B: nucleus, mitochondria, cell membrane
c and d both have chloroplasts which are unique to plant cells
a is wrong because only plant cells have cell walls
I think it’s Ribosomes but I could be wrong .. if so sorry
Answer:
A chemical element is a type of atom with the same number of protons in their <u>atomic</u> nuclei.
Explanation:
For an example, the atomic number of Chlorine is 17, and there is 17 protons in Chlorine.
If you have any questions feel free to ask in the comments.