Answer is: B. antimony and tellurium.
1) Iodine (I) is an element with atomic number 53 (53 protons and 53 electrons), it is in group 17 (halogen element) and period 5 (principal quantum number n = 5, which means it has 5 electrons shell) of Periodic table.
Electron configuration of iodine atom: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁵.
2) Tellurium (Te) is an element with atomic number 52 (52 protons and 52 electrons), it is in group 16 (chalcogens) and period 5 (principal quantum number n = 5, which means it has 5 electrons shell) of Periodic table.
Electron configuration of tellurium atom: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁴.
3) Antimony (Sb) is an element with atomic number 51 (51 protons and 51 electrons), it is in group 15 (pnictogens) and period 5 (principal quantum number n = 5, which means it has 5 electrons shell) of Periodic table.
Electron configuration of antimony atom: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p³.
