Mendel knew that the variations in the offspring
generations resulted from his experiments
because he
•a. allowed plants to cross-pollinate.
.b. ensured that plants self-pollinated.
.c. controlled the fertilization process.
.d. changed the growing conditions.

controlled the fertilization process.

Explanation:

Mendel took precautions to avoid contamination by pollen through self pollination of the P generation. He controlled the fertilization processes between the plants. He self pollinated the first pureline varieties to form the P generation. He then cross pollinated them to get F1 generation. Every step of his experiment was controlled.

answer: grassland biomes are closer to the equator and receive more rain.

grasslands are biomes that are dominated by grasses rather shrubs and trees. savanna are biomes that exhibit grasses, shrubs and small tree as vegetation. grasslands are located near the equator of the earth. these are found in north america. savanna biomes are found in africa, south america, australia and india. grassland exhibit moderate climatic conditions, it receives   amount of rainfall higher than savanna.   therefore, savanna exhibit dry and hot climatic conditions.