D. More economically developed countries
Except the c) sweat gland
There are three types of hazards
- physical such as knives, filet bone
- chemical such as cleaner, chlorine (chemical substances)
- biological such as bacteria, mold (live organisms)
Because filet bone is a physical hazard the answer is D (filet bone)
<h3><u>Answer</u>;</h3>
Key
A sorting device that is useful in classifying by observation is a <u>key</u>.
<h3><u>Explanation</u>;</h3>
- <em><u>Classification key or taxonomic key is a device that is used by scientists to identify unknown organisms. </u></em>
- They are constructed so that the user gets a series of choices about the characteristics of the unknown organisms.Thus, by making the correct choice at each step, one is led to the identity of the specimen.
- Therefore<u><em>, keys can be used to identify a living organism or determine which group it belongs to</em></u> by answering questions on the key about characteristics of living things.