I need help!

1.Which of the following events would least likely cause a phenotypic change?
Select one:
a. base substitution
b. base addition
c. base deletion

3.During the process of translation, ____________ "reads" the mRNA.
Select one:
a. a ribosome
b. ligase
d. helicase

8.The process of translation involves the cooperation of:
Select one:
a. 64 possible combinations of bases and 20 possible Amino Acids
b. 124 possible nucleotides and 21 p[ossible Amino Acids
d. 4 combination of bases and 64 Amino Acids