an IQ test is given on a tuesday, when given the test again on thurs the child scores differently, this is an issue of what? function, reliablity, observation or reflection?
I don't like any of your choices. My IQ scores have varied by as much as 20 points. The major difference was me -- whether I was tired or had other things on my mind.
This site explains the answer your teacher probably wants.
http://psychology.about.com/od/researchmethods/f/reliabilitydef.htm