<span>ecosystems , is your answer if I'm not wrong
</span>
Yearly dental visits are a part of good dental hygiene because the dentist will check for cavities, fix them, clean your teeth very thoroughly (or whitening treatment), and check the progress and movement of your teeth. They can also recommend when dental surgery is necessary, for instance, if you have extra teeth that can be removed or when your wisdom teeth are coming in. Hope this helps! :)
The major difference between compost and green manure lies in their composition. While green manure is made from animal-based waste products such as urine and feces. Adding compost to the soil enriches the soil with organic matter while green manure increases the nitrogen level of the soil.
I believe the answer is b