A part of the periodic table is shown.
A portion of the first two columns of the periodic table is shown. Column one from top to bottom reads 11 sodium, 19 potassium, and 37 rubidium. Column two reads 12 magnesium, 20 calcium, and 38 strontium.
Which of the following elements is more reactive than the others?
a) Calcium (Ca)
b) Magnesium (Mg)
c) Potassium (K)
d) Sodium (Na)