The sampling methodology used by the researcher is valid. The researcher has selected the participants of the study based upon the requirement of the study. The participants chosen for the study include forty two full term five months' old girls and boys. They include 21 boys and 21 girls. The study also excludes the participants based upon experimental errors and fussiness which determines the validity of the sampling in the study. The recruitment of the participants for the study was obtained through the birth records of the infants by their countries. The final sample is ...
