Final answer:
The yellow tint and aroma from the apple pieces are due to ethylene gas exposure, which speeds up ripening and affects color and smell. Ethylene is a natural plant hormone that can cause fruits to ripen or over-ripen when trapped in an enclosed space with them.
Step-by-step explanation:
Apple pieces removed from a bag might have a slightly yellow tint and a distinctive aroma primarily due to ethylene gas exposure. Ethylene is a volatile gas associated with fruit ripening, flower wilting, and leaf fall. When an apple ripens, it naturally produces ethylene, which can further speed up the ripening of the same apple or nearby fruits.
If you put a ripe apple or banana in a closed container or paper bag with another unripe fruit, the ethylene gas trapped inside will cause the unripe fruit to ripen more quickly. This is also why refrigeration and ventilation are important in preserving fruits to slow down these chemical reactions and to remove the ethylene gas, respectively.
In summary, the correct answer to why apple pieces might have a slightly yellow tint and a distinctive aroma after being removed from a bag is option C) Ethylene gas exposure.