Question: Haploid mutants A, B, and C are Arginine auxotrophs. You construct a yeast genetic library by dig…

Haploid mutants A, B, and C are Arginine auxotrophs. You
construct a yeast genetic library by digesting wild-type yeast
chromosomes with EcoRI and ligating the DNA fragments into vectors.
This library is then transformed into large clonal populations of
each mutant strain, and the transformed yeast are grown in minimal
media. Rescued colonies are successfully grown from Mutants A and
B, but not from Mutant C. Consider the following hypotheses for why
Mutant C could not be rescued.

I. The library created by EcoRI digestion did not contain a
working copy of the defective gene that is in Mutant C.

Is this a reasonable hypothesis? (choose one)

YES (or) NO

If yes, describe an experiment to
test this hypothesis. If no, explain why not.

II. Mutant C is a double mutant and has defects in two genes
necessary for Arginine synthesis.

Is this a reasonable hypothesis?
(choose one)

YES (or) NO

If yes, describe an experiment to test this hypothesis. If no,
explain why not.

III. There is a problem with the vector, making it incapable of
transforming genes into Mutant C.

Is this a reasonable hypothesis? (choose one)

YES (or) NO

If yes, describe an experiment that could prove this hypothesis.
If no, explain why not.