Final answer:
Group V-A (15) elements achieve a noble gas configuration by gaining three electrons to complete their valence shell octet. So the correct option is 1.
Step-by-step explanation:
The electronic change that will cause a group V-A (15) element to achieve a noble gas configuration is gaining three electrons. Group V-A elements have five valence electrons and need three more to complete their octet, which gives them the stability of a noble gas electron configuration. From our understanding of periodic trends and the octet rule, nonmetals on the right side of the periodic table, like those in groups 15-17, gain electrons to achieve the valence electron configuration of the nearest noble gas.