Answer:
<h2>a) Evolution</h2><h2>
b) harmful recessive traits become uncommon</h2>
Explanation:
<h2>
Experiments on mice should be stopped. I had a pet as a white mouse. He died because of depression 2 months ago. I am sad about seeing this mouse being treated cruelly in the lab.</h2>
First one is a and second one is b
The answer is the first option.
"They perform well only at very low temperatures."
Despite of advantages of Superconductors such as power and cost efficiency, these conductors have drawbacks. Semiconductors have restricted operation range of operating temperatures. They are required to work at very low temperatures.