Answer: B
Explanation: Traits usually die off when they are unneeded by the organism, or if the trait causes harm to the organism's survival. Through natural selection, over time, the organisms with the best combination of traits for its survival will become the dominating species, and those with weaker traits may not survive long enough to pass off their traits to future offspring.
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Answer:
Option (C)
Explanation:
Blood smears usually refers to the blood test that is being conducted in order to determine if there is any abnormality or irregularity in the blood cells. This test is conducted in the laboratories by using the slides.
After the test is done, these slides of blood smears are usually disposed of according to the instruction given by the teachers. It is because these slides have sharp edges and must be carefully handled. It can cause cut in the fingers and as these slides are comprised of infectious substances, it can affect other individuals, causing various types of diseases.
Thus, they must not be disposed of here and there, rather they should be disposed of according to the teacher's instruction.
Hence, the correct answer is option (C).