Dr. Maxwell performed several experiments which seem to indicate that eating chocolate is always bad for your health. How should
other scientists respond to Dr. Maxwell's research?
OA. They should accept Dr. Maxwell's research without argument
OB. They should ignore Dr. Maxwell's research,
Oc. They should change Dr. Maxwell's results in secret
OD.
They should try to reproduce Dr. Maxwell's research to verify his results,

D. They should try to reproduce Dr. Maxwell's research to verify his results

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6