Which sequence shows a substitution mutation of a section of this dna?

I took a chance with the answer given by Madison0000006.

It is correct.  For those who want to know what the options were?

A.  A-C-T-G-G-T

B.  A-C-T-G-G-A

C.  A-C-G-G-A-T

D.  A-C-T-G-C-G-A-T

Explanation:

because they are eaten by the frog and the frog getseaten by the snake and the snake by the eagle

since there are no options posted i'll give you a few examples.

a dolphin's flipper, bird's wing, cat's leg.