The thumb bone is part of the appendicular skeleton, while the sternum is part of the axial skeleton. Therefore, the correct answer to the above question is option b.
Explanation:
The human body is considered to have 206 types of bones. The skeleton system is considered to be the basic structure of the body. The whole skeleton system is comprised of bones. The whole skeleton system is divided into two reason which are appendicular skeleton and axial skeleton.
Axial skeleton consists of bones which are axial in nature and helps the human body to stand firm and straight on the ground. The “appendicular skeleton” consists of bones which are other than axial bones like hands, fingers, feet etc.
The parents are of genotype heterozygous dominant and homozygous recessive. Supposing the dominant allele is N and the recessive allele is n, one of the parents will be Nn while the other nn. The phenotypic (based on visible characteristics) ratio will be 1:1 for dom/rec and rec/rec
