The best statement that describes lightning is A. It is one of the most dangerous parts of a thunderstorm. Lightning, although often thought to always strike the Earth, can actually occur in the same cloud (intracloud) and between clouds (cloud to cloud). It is caused by the electrostatic discharge between charged particles in the atmosphere.
If you're a carrier, you're a heterozygote...So let's say S is normal allele and s is diseased allele, then you'd be Ss. Someone with sickle cell anemia would be ss (homozygous recessive)
