Read the introduction (paragraphs 1-5). What does this section explain that other
sections do NOT?
А
a description of which elements can be
affected when nuclear fusion occurs inside a
star
B
a comparison between the amount of
energy inside a star and the amount used to
power a city
С
an explanation of the elements that cause
stars to heat and collapse during nuclear
fusion
D
a series of events that triggered the creation
of our solar system millions of years ago

the seeing the electronic configuration we can say that the element is fluorine.

fluorine is the most electronegative element in the periodic table.

but by only seeing the configuration we cannot say about its reactivity because we don't know if its configuration after excitation or by addition of electrons.

but if not then, it is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. as the most electronegative element, it is extremely reactive: almost all other elements, including some noble gases, form compounds with fluorine.