1. Which of the following statement(s) is/are correct for the human genome?
a) Most of the DNA codes for proteins
b) Most genes contain introns
c) Extons define where and when genes are to be activated
d) a and b
e) b and c

ps: what does introns and extrons mean?

2. Which of the following descriptins for the DNA structure is correct?
a) It is double-standed with anti-parallel helix
b) It is a polymer of nucleotides linked from one nucleotide to the next by
phosphodiester linkage
c) The polymer carries a net positive charges in its bases
d) a and b
e) b and c

ps: what does c) mean? can some body translate it into Chinese or explain it more detailedly for me?

3. Which of the following types of RNA is Not involed in the process of translation?
a) Ribosonal RNA
b) Transfer RNA
c) Messenger RNA
d) Small nuclear RNA
e) All of above are involved

ps: is Ribosonal RNA involved? if so, what is its functionality during the process?