Final answer:
The relatedness between organisms is determined by their evolutionary history and genetic makeup. The mouse and cow may be the least related out of the four choices if they have the most number of differences.
Step-by-step explanation:
In biology, the similarity or relatedness between organisms is determined by their evolutionary history and genetic makeup.
The more similar the DNA sequences and amino acid sequences are between two organisms, the more closely related they are considered to be.
Therefore, if the mouse, cow, and the other choices are being compared based on the number of differences they have, it's possible that the mouse and cow are the least related out of the four choices.