Solutions of which ion produce a red colour when vapourized in a Bunsen burner flame?

Calcium ions produce a red colour when vaporized in a Bunsen burner flame. A blue flame is produced by copper, a red flame by lithium and strontium, an orange flame by calcium, a yellow flame by sodium, and a green flame by barium. When barium or a barium salt is added to a flame, the flame takes on a distinctive green colour. Similar to that calcium gives off a distinctive brick red colour, strontium gives off a crimson red colour, while radium gives off a crimson colour. Hence, option A is correct.