Question

Which of the following is a biotic limiting factor for a plant population in an ecosystem?

Access to sunlight
Birds that disperse seeds
Availability of soil minerals
Disease-causing bacteria

Answer 1

Access to sunlight is an abiotic factor, so not that one.
Bird that disperse seeds seems a likely answer - the birds are biotic and they affect the plant population because of how they disperse seeds.
Availability of soil minerals is abiotic, not that one either.
Disease-causing bacteria is another likely answer because it's biotic and it definitely affects plant population.
I think D is correct because bacteria are a living (biotic) factor in ecosystems and they affect plant populations

Answer 2

Answer: Disease causing bacteria.

Step-by-step explanation:

A limiting factor can be define as the factor which can limit the growth, distribution or abundance of population of a species in an ecosystem.

A limiting factor can be living (biotic) and non-living (abiotic).

Among the options given, disease causing bacteria is the correct option. As bacteria is disease causing pathogen which is a biotic limiting factor it will consume nutrients from plants result in death of plants and decline in their distribution in ecosystem.