Which of the following is the best description of the cane toad’s introduction to australia?
a.
it was a successful biological control mechanism for cane beetles.
b.
it was a failed biological control mechanism for cane beetles.
c.
it was a successful method for reducing freshwater crocodile populations.
d.
it was a failed attempt to eradicate south american fire ants.

b.  It was a failed biological control mechanism for cane beetles.

Explanation:

An invasive species is the one which is introduced either intentionally or accidentally into a new habitat is responsible for causing harm to the native species by competing it for resources.

A cane toad was an invasive species native to Florida and was introduce to Australia to get rid of cane beetles damaging the sugarcane crops.  These toads were capable to control the beetles to some extent but they became competitive with the native species. They were poisonous and were responsible for killing the other organisms of the native land.        

americans began to notice growing differences between the northern and southern sections of the country. there were more people living in cities in the north, which made it more urban. more people lived on farms in the south, which made it more rural. while many people were farmers in the northern states, there were now other ways to make a living, such as working in mechanical cotton gins factories manufacturing cloth, tools and other goods. people in the north supported high tariffs on goods imported from europe because the extra cost encouraged people to “buy american” instead. in the southern states, planters did not like tariffs because they sold most of their production to europe and bought their tools from there as well. southerners believed the protective tariff was something that only northern factory owners keep their profits high. so the southern politicians came up with an idea. they would opt out. they would simply ignore the protective tariff. it was ‘null and void’ in south carolina. the state would not collect the taxes on goods imported into south carolina, no matter what the president said they had to do. this decision led to the nullification crisis.

the correct answer is b