Answer: Choice D) TATCCA
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Explanation:
In DNA, there are four basic building blocks
- Adenine
- Thymine
- Guanine
- Cytosine
We can abbreviate them to A, T, G, and C in that order.
The order I mentioned is often what biology and chemistry textbooks go with because A pairs with T as a complementary base pair, and G pairs with C.
So if one strand has A, then directly across from it will be T, and vice versa. Refer to the diagram below. The image is not mine and something I searched for after typing in "DNA diagram".
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Now to the problem at hand. We're given that one strand has the sequence ATAGGT
Since A is listed first, directly opposite this must be T which is on the other strand.
So T is the first letter in the answer. Choice D is the only one that fits, which is why it's the final answer.
