1. Take a look at all the elements in period 3. What do you notice? * 5 points
A. They have the same number of energy levels
B. The number of energy levels decreases as you go across the period from left to right
C. They have the same number of valence electrons
D. The number of valence electrons decreases as you go across the period from left to right

D

Explanation:

beacause all the elements in period 3 has different valence electrons hence you look at the first element in period 3 is sodium which has a valence electron of 1 when you go across the period to the right their valence electron decreases to be negative

D is the correct answer i hope this is correct

i would say b

explanation:

but i think i would need more information than that

1 is the answer to this problem