This can be a tricky one. The passage states that scientists who claim "creating a computer program that encapsulates the information contained in the human genome" is "all that is required for making an artificial intelligence" are mistaken. The evidence given to support this is the fact that "the operation of the human brain is governed by the interactions of proteins whose structures are encoded in the human genome." Therefore, there must be a disconnect between the interactions of proteins whose structures are encoded in the human genome and merely the information contained in the human genome. In other words, the interactions of the proteins must not be controlled fully by the information in the human genome. This is what (B) suggests, which is why it is correct. (A) is incorrect because it is too far-reaching. We do not have enough information to say that "the functions of the human brain are governed by processes that cannot be simulated by a computer." Perhaps other functions can be simulated by a computer, and perhaps this function (the interaction of proteins) can be simulated by a computer if more than only the information contained in the human genome is incorporated into the programming.
Does that make sense? Please let us know if you have any other questions!