Which of the given elements A,B,C,D and E with atomic numbers 2,3,7,10 and 30 belong to the same period?

Q. Which of the given elements A,B,C,D and E with atomic numbers 2,3,7,10 and 30 belong to the same period?
A. A,B,C
B. B,C,D
C. A,D,E
D. B,D,E
Answer: B,C,D