Thousands of years ago, some people began dairy farming. This coincided with a number of mutations in a particular gene that resulted in these people developing the ability to digest dairy milk.
Based on the given passage, which of the following can be inferred?
Answer
(D)
Explanation
The passage says that mutations in one gene gave the early dairy farmers the ability to digest dairy milk. So, in human beings, the ability to digest dairy milk came from a mutated gene, which is option (D).
(A) fails because the passage speaks only of some people. (B) contradicts the passage, since these people did gain the ability. (C) goes beyond the passage, which never says that digesting milk is essential for humans.
Answer: D