Question

I am really leaning towards 2 but I don't think it would work. I am now leaning towards Rnai maybe just for its introductory abilities.
What technique could scientists use to determine the location of the disease gene in the human genome?
1. RNAi
2. use microarray to compare mRNA levels in normal and diseased individuals
3. use microarray to compare SNP profiles of family members from the pedigree
4. cloning by complementation
5.cloning by protein expression

Answer 1

RNAi wouldn't let you pin point the location..
using a microarray would let you look for the sequence in question, but you would have to do the whole genome, or most of it

Answer 2

comparing single nucleotide polymorphism profiles, could help you narrow down the location ..

cloning by complementation would work if you have some sort of identification mechanism (e.g. molecular beacon) that would tell you where it was upon hybridization

i'm not sure what cloning by protein expression is