Plants in the tundra biomes have had to adapt to live long periods of time without a. cool temperatures b. sunlight c. oxygen d. water

B. sunlight

Explanation:

The tundra is one of the harshest biomes. The main reason for this are the climate conditions. The tundra is cold for most of the winter as it is winter for most of the year, having only a very short ''summer'', which is still mild during the day and cold during the night. Also, for several months, the tundra experiences a period where it is constantly night, so the plants had to adapt to hibernate during this period as they can not perform photosynthesis without the sunlight.

the answer would be b).