from o level syllabus:
a plastic rod rubbed with a dry cloth becomes positively
charged.
so, electrons can only be lost or gained since protons are fixed
in place..
MCQ included both options of loss/gain of electrons, dont know
which answer to choose, kindly instruct me 
secondly, charging by friction/induction, which method works
best for electrical conductors and insulators, and why?
i know that charging by friction for conductors is not viable
because the hand holding it would act by earthing the conductor due
to the electrons being transferred via conduction, whereas this
wouldnt happen for insulators.
for induction, it is easy to use induction on conductors, but
difficult to use induction on insulators. need to know why.
ok this is a pretty long post, ty for any help and your time
