Final answer:
Mg (magnesium) and Ca (calcium) are the pair of elements with similar properties, as both are alkaline earth metals with similar characteristics and are adjacent in the periodic table.
Step-by-step explanation:
Elements with similar chemical properties are typically found in the same group (column) on the periodic table. In the context of the given choices, the pair of elements that has similar properties is Mg, Ca. These elements both belong to the group known as the alkaline earth metals. This group includes beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra), all of which share common characteristics. They are shiny, good conductors of heat and electricity, and tend to form compounds with oxygen in a ratio of one metal atom to one oxygen atom. Additionally, Mg and Ca are close to each other in the periodic table, further indicating their similar properties.