Answer:
Sunlight
Explanation:
Plants are autotrophs which makes their own food in the presence of sunlight and the process is called photosynthesis. Sunlight is very important for the process of photosynthesis.
So, the only abiotic factor from the options that could limit the growth of the plant population is sunlight. plants can not make their food without sunlight and no food means no growth of plant population.
Hence, the correct answer is "Sunlight".
