Answer:
the only correct is C, If the complementary strand were present, the number of purines would be equal to the number of pyrimidines.
Explanation:
You must always remember that in nucleic acids the rule of base complementarity is met. Whenever there is a puric base, there will be a pyridine in the complementary strand.
The purines are A and G
The pyridunas are C and T
Possible unions are A - T or C - G.
In the sequence TACGTAACGTA there are 6 purines and 5 pyridines.
When you see the complementary chain: ATGCATTGCAT, there are 6 pyridines and 5 purines.
As you can see, as long as there is a double chain, for each purine, there will be a pyridine on the other side.