A healthy, young couple are both carriers (Aa) heterozygous of cystic fibrosis. Cystic fibrosis is a recessive disease. What is the chance that each
of their future children will inherit this serious illness?

b. the carbon cycle ensures living things have a source of hydrogen

the correct answer is option b

behavioral response need communication and thus co-ordination at several levels such as interaction among cells, organ system and the entire organism.

behavioral response produces both internal and environmental stimulus.