DrLen Wants to Determine Whether or Not Dextrin Causes People

Multiple Choice

Dr.Len wants to determine whether or not dextrin causes people to lose weight.He gives 10 subjects dextrin and 10 subjects a placebo.He measures their weight every day (since weight seems to fluctuate daily) until the experiment is discontinued (after 4 weeks) .In Dr.Len's study what are some disadvantages with using this particular design?

A) significant amount of variance in subjects occurs
B) carry-over effects
C) a large subject pool is needed
D) Both a & c
E) All of these