Answer;
D. Positive particles in the nucleus are attracted to shared electrons, so the atoms stay close together
Explanation;
-Covalent bonds hold atoms together because the attraction between the positively charged nuclei and the negatively charged shared electrons is greater than the repulsions between the nuclei themselves.
-The attraction between the positively charged nuclei and the negatively charged shared electrons is greater than the repulsions between the nuclei themselves.
-As two atoms approach each other, the electrons in their outer shells start to notice the nucleus of the other atom. As a result, they become attracted not only to their own nucleus, but to the nucleus of the other atom as well. The electrons then tend to spend more of their time in between the two nuclei, instead of just around their own nucleus.