Even when the supply of inorganic nutrients to the surface is high, due to for example upwelling, the absolute concentration of nutrients in the surface may still be low.

Upwelling brings those lost/sunk nutrients, plankton and carcasses to the surface. The surface then becomes feeding grounds for fish and other ocean life.    

its 42

i say its d?

ans.

gregor john mendel is known for study of inheritance in pea plants. he used garden pea plant for his study, having alternative traits for various characters. he performed cross-breeding in pea plants to check how characters are transmitted between parents to offspring, such as cross between pure tall and pure dwarf plant. mendel studied the inheritance patterns in pea plants for various generations.

thus, the correct answer includes options and f).