Final answer:
DNA strand polarity refers to the 5' to 3' orientation of nucleotides. The antiparallel nature of DNA strands means they run in opposite directions. Strands are complementary because specific nucleotides match (A with T and C with G), according to Watson-Crick base pairing. Option C is correct.
Step-by-step explanation:
When discussing that a DNA strand has a polarity, we refer to the directionality of nucleotides, meaning that each strand has a 5' end with a phosphate group and a 3' end with a deoxyribose sugar. The term antiparallel describes the orientation of two DNA strands in the double helix, indicating that they run in opposite directions: one strand runs 5' to 3' while the other runs 3' to 5'.
The strands being complementary to one another means that they form matching base pairs, where adenine (A) always pairs with thymine (T), and cytosine (C) pairs with guanine (G). A DNA strand has polarity signifies each strand's orientation from 5' to 3'. Two DNA strands being antiparallel means they align in opposite directions.
Lastly, the complementarity of DNA strands indicates that each nucleotide on one strand pairs with a specific counterpart on the other, which corresponds to choice C) 3' to 5' arrangement; Opposite directions; Matching base pairs.