The best method to determine the homozygosity and heterozygosity of an individual is
a)	Self-fertilisation	b)	Back cross	c)	Test cross	d)	Inbreeding

(b)

The best method to determine homozygosity and heterozygosity of an individual is back cross.

Crossing of  (dominant phenotype) to any one of the parent called back cross and when phenotype of crossing parent is recessive than this is called test cross. The progeny of such cross can easily be analysed to predict the genotype of test organism