How does the amount of p-nitrophenol relate to the cellobiase activity?

this is true, assuming that the allele is completely recessive and incomplete dominance is not a factor.

. ph changes the ability of them he enzyme to dissolve in water.

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).   so the answer is a.