From their location in the Periodic Table, which of the following elements tend to lose 2 electrons when they form ions?A Beryllium and CalciumB Oxygen and SeleniumC Beryllium and OxygenD Calcium and Selenium

To determine which elements tend to lose 2 electrons when they form ions, we need to look at their location in the Periodic Table.

Option A includes Beryllium and Calcium. Beryllium is located in Group 2, while Calcium is also in Group 2. Elements in Group 2 tend to lose 2 electrons to achieve a stable electron configuration. So, option A is a possible answer.

Option B includes Oxygen and Selenium. Oxygen is located in Group 16, while Selenium is in Group 16 as well. Elements in Group 16 tend to gain 2 electrons to achieve a stable electron configuration, rather than losing them. Therefore, option B is not the correct answer.

Option C includes Beryllium and Oxygen. As mentioned earlier, Beryllium tends to lose 2 electrons, but Oxygen tends to gain 2 electrons. So, option C is not the correct answer.

Option D includes Calcium and Selenium. Calcium, as mentioned earlier, tends to lose 2 electrons. Selenium, on the other hand, is located in Group 16 and tends to gain 2 electrons. Therefore, option D is not the correct answer.

Based on the analysis, the correct answer is option A: Beryllium and Calcium.