Which one from those given below is the period for Mendel's hybridisation experiments?

When an allele fails to express itself in the presence of another allele, the former is said to be

The cross used to determine whether a dominant phenotype is homozygous or heterozygous is called ......

The term "genotype" was coined by

Johann Mendel is considered a genius much ahead of his time, as he proposed the concept of "factors" (now called genes) based on the fact that . . . . . . .

Which of the following is the most suitable medium for the culture of $Drosophila$ $melanogaster$?