Recall the three discoveries Erwin Chargaff made while studying DNA: the total amount of pyrimidines (T+C) equals the total amount of purines (A+G), the amount of T equals the amount of A, and the amount of G equals the amount of C. These three "rules" led to what conclusion(s) about DNA base pairing?

A purine base pairs with a pyrimidine base.

A pairs with T.

G pairs with C.

All of the answer options are correct.

None of the answer options is correct.

All of the answer options are correct.

Explanation:

Chargaff contributed in understanding the structure and composition of DNA with his discoveries. He discovered that purine and pyrimidine bases are in equal amounts in a DNA molecule. He also discovered that amount of Adenine base (A) is equal to amount of Thymine base (T). It means that A pairs with T. Since A is a purine and T is a pyrimidine it also implies that purine base pairs with a pyrimidine base. This conclusion can also be arrived by taking in consideration the other base pair which is G (purine) and C (pyrimidine).

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