This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Molecular Genetics, Subject name: Biochemistry
About DNA which of the following is true: 
Select and explain. 
A. The nucleotide of one strand form bonds with nucleotide of opposite strand., B. Cytosine and Uracil differ by one ribose sugar, C. The information from DNA is copied in the form of tRNA, D. Each nucleotide pair includes two purines.
A: The nucleotide of one strand form bonds with nucleotide of opposite strand.
Answer: A: The nucleotide of one strand form bonds with nucleotide of opposite strand. 
Explanation: Ans. A. The nucleotide of one strand form bonds with nucleotide of opposite strandOne strand of DNA join with other strand of DNA by means of Hydrogen bond between the bases.Cytosine and uracil differ by amino group.The information in the DNA is copied in the form of mRNA. Each nucleotide pair includes one purine and one pyrimidine.