Question

we notice that co2 changes over the course of the year that passes which is regular but what are most likely caused by?A. burning of fossil fuels B. seasonal trends in tourismC. forest firesD. photosynthesis and respiration

Answer 1

D. photosynthesis and respiration

Step-by-step explanation

Levels of carbon dioxide in the atmosphere rise and fall each year as plants, through photosynthesis and respiration, take up the gas in spring and summer and release it in fall and winter. Now the range of that cycle is expanding as more carbon dioxide is emitted from burning fossil fuels and other human activities.