As scientists have developed more productive crop varieties, farmers have switched from growing many traditional varieties to new high-yield varieties. for example, in peru, the indians once grew 500 native varieties of potatoes. that number has been reduced to about twenty major potato varieties, worldwide. why is it potentially dangerous to reduce the number of crop species in potatoes?

C-

Explanation:

It makes the overall crop more susceptible to pests or disease. One variety of potato may be less susceptible to potato blight than another, so it may survive and keep producing potatoes, whereas the other one died.

the atomic number of magnesium is 12. its nucleus must contain 12 protons and no electrons. the atomic number of an atom is determined by the number of protons.

magnesium is an electrolyte injection commonly used to treat low magnesium levels in your blood. it is also used to prevent or control seizures in women with preeclampsia or eclampsia.