Why can mRNA leave the nucleus, but DNA cannot leave the nucleus?
A. DNA is single stranded and is too long to leave the
nucleus.
B. RNA is singled stranded, DNA is double stranded, so
RNA is smaller than DNA.
C. DNA can leave the nucleus through special openings in
the nuclear membrane.
D. DNA and RNA can both leave the nucleus.

I would say B.(RNA is singled stranded, DNA is double stranded, so

RNA is smaller than DNA.)

RNA is a single strand and can leave the nucleus easily but the DNA is double strands that are twisted together and are big and cannot leave the cell

B

Explanation:

Your DNA is stored in a double helix formation. Which means it has two long strands and would be too long to leave the nucleus. C and A are incorrect. DNA is double stranded, so we can eliminate A. There are NO special openings in the nucleus. Only the cell membrane. C is eliminated.

Option D is incorrect because DNA is transcribed into the cell membrane, there is no way for it to leave. RNA is a single strand.