Biology answer please?

Question

here are 3 questions i need help with..

a) DNA technology has many medical applications. Which is not done routinely at present:

1) production of viral components for vaccines

2) introduction of genetically engineered genes into human gametes

3) prenatal identification of genetic disease genes

4) genetic testing for carriers of harmful alleles

b) What is the advantage of being able to clone the gene for human insulin:

1) human insulin is more variable than other sources of insulin, so cloning would provide a greater chance of obtaining a form that can be used by the diabetic's muscles

2) there are too few cows, pigs and horses to provide an adequate supply

3) human insulin is less likely to provoke an allergic response than cow, pig or horse insulin

4) cow, pig or horse insulin cannot keep a diabetic alive for more than 3 months

c) A man carries an x-linked recessive allele

1) all of his daughters would get the allele

2) his daughters would have a 50% chance of getting the allele

3) all of his sons would get the allele

4) all of his children would get the allele

thanks

Answer 1

1 is answer 2

2 is answer 3

3 is answer 1 or 2 because there are two ways to interpret the question: in answer 1 you can say that all of his daughter will get HIS recessive allele but answer 2 could also be right because his daughters will have a 50% chance of having the allele activated, because females deactivate one of the x chromosomes in barr bodies. if i would pick an answer i will pick number 1.

Answer 2

A - 2

B - 3

C - 2

Answer 3

a. 2

b. 3

c.  2