Working through the possibilities

Science tip:

Sometimes the question requires you to go through a lot of detail and analysis. Here’s an example. Instead of lamenting why the boys didn’t do the experiment with one object at a time, let’s dive right in.

Referencing the images from left to right, top to bottom:
– Image 2 shows C and D are conductors.
– Image 3 shows A and D are conductors.
– Image 6 shows F and C are conductors.
Therefore A,C,D,F are conductors.
– Image 1 shows B is non conductor, since A is.
– Image 4,5 shows E is non conductor, since A and F are.
Therefore B and E are non conductors.

Therefore ans is (4) Denise is correct.