Answer:
B: They are highly reactive
Step-by-step explanation:
Sodium(Na) and potassium(K) are in the same family/group which is the Alkali Metal group. These groups have their ability to displace H2(g) from water and create a basic solution. Alkali metals are also known to react violently and explosively with water. This is because enough heat is given off during the exothermic reaction to ignite the H2(g). Therefore, they are similar because of their reactivity.
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