Science is way to broad of a subject to define a specific thing you are doing. It is the equivalent of someone asking what book you are reading and you replying, "a novel." Your experiment could also have life-changing effects on someone, so to underrate it as "doing science" would simply be inaccurate.
The answer is (3) An electron in the third shell has more energy than an electron in the second shell. The energy of electron will increase when number of shell increase.
