In the periodic table, how are elements in the same group related to each other? a. they have the same atomic mass. b. they have very different properties. c. they have the same atomic number. d. they have very similar properties.

D. They have very similar properties.

Explanation:

A. They have the same atomic mass.

 ⇒ This is false, every element has a different atomic mass.

B. They have very different properties

 ⇒ This is false. elements in the same group have similar properties

C. They have the same atomic number.

⇒ Every element has a unique and different atomic number

D. They have very similar properties.

 ⇒ This is correct. Elements in the same group usually have similar properties, because they have the same number of electrons in the outermost electron shell.