The first items in the Biology E/M test are arranged in sets with common answer choices. These items appear in the core section of the test. Remember, these are not MATCHING challenges — each answer choice can be used once, more than once, or not at all.
A nitrogenous base that occurs in DNA in equal quantities with guanine
Select an Answer
The correct answer is cytosine. The only base that is always found in equal quantities with guanine is its complement, cytosine (recall that the nitrogenous bases in DNA pair, A with T and C with G.)