Answer:
option d is correct. the existence of land bridges between continents.
Explanation:
landland bridge theory which was used to explain why species would end up continents over, such as mammoth travelling to North America, thisthis theory was based on the idea that water eventually Rose to cover these bridges rather than the at having individual plates that moved away from each other.
Plant cells have what is perhaps the most complex outer coverings. Plant cell walls are made largely of cellulose which forms strong, highly rigid, almost indigestible coverings that protect the cell and gives it shape.
Chlamydia is a disease transmitted by sex with someone infected. Its caused by bacteria and often is asymptomatic.
Treatment is with antibiotics, and it's essential to know if one is infected because in women can cause infertility, and in males can cause urethra complications like inflammation and obstruction.
A string of nucleotides that hold information is called a gene. :)
