Which of the following statements about the properties of elements in Group I or Group VII is correct?
- ABromine displaces iodine from an aqueous solution of potassium iodide.
- BChlorine, bromine and iodine are diatomic gases at room temperature.
- CLithium, sodium and potassium are soft non-metals.
- DLithium, sodium and potassium have an increasing number of electrons in their outer shells.