Biotic factors are those that are living in an ecosystem, such as plants and animals, while abiotic factors are those that are not, such as rocks, temperature, water, sunlight, soil etc.
C is correct for number 2 because broadleaf trees are a biotic factor, while precipitation, or rainwater, is abiotic.
A is incorrect because both are biotic factors, since both are living
B is incorrect because both are abiotic factors, since both are nonliving
D is incorrect because both are biotic factors, since both are living