In each group, name any answer which matches the first category to reveal the second category, then name any answer which applies to both categories to reveal a third, and so on.
Chemistry is my kryptonite. I guessed my face off and somehow managed to get 16/20, despite not knowing what an atomic number is or actinides, or what element is in what row. Who needs brains when you're born lucky ;)
The easiest way is to separate answers by | (the pipe) in Step 2, this will produce auto typeins in Step 3, separating one answer per line. You can then set this to custom (to make sure it doesn't change) and then go back to Step 2 and change the visible text to be a check character.
Actinides or Lanthanides. I made some lucky guesses.