How is dna copied?

a. the antisense strand of dna is used as a template to create both strands of the new double helix.
b. the sense strand of dna is used as a template to create both strands of the new double helix.
c. each single strand of dna is used as a template to create a complementary strand of dna.
d. the mrna made from the dna is used as a template to create a complementary strand of dna.

The DNA is copied by B: The sense strand of DNA is used as a template to create both strands of the new double helix.

Explanation:

Ok, the DNA is "copied" in the tanscription process. The transcription is the process by which the information in a strand of DNA is copied into a new molecule of messenger RNA (mRNA). Also, the DNA safely stores genetic material.

During the process of transcription a single strand of RNA is synthesized using a double stranded DNA molecule as a template.  The two strands of the DNA molecule are separated from one another, exposing the nitrogenous bases. Only one strand is actively used as a template in the transcription process, this is known as the sense strand, or template strand. The complementary DNA strand, the one that is not used, is called the nonsense or antisense strand.

ok yes, but what is the question? as soon as you ask the actual question i will answer it. : )