Reading Comprehension

The idea of the brain as an information
processor-a machine manipulating blips of energy
according to fathomable rules-has come to
dominate neuroscience. However, one enemy of
the brain-as-computer metaphor is John R. Searle,
a philosopher who argues that since computers
simply follow algorithms, they cannot deal with
important aspects of human thought such as
meaning and content. Computers are syntactic,
rather than semantic, creatures. People, on the
other hand, understand meaning because they have
something Searle obscurely calls the causal powers
of the brain.
Yet how would a brain work if not by reducing
what it learns about the world to information-some
kind of code that can be transmitted from neuron
to neuron? What else could meaning and content
be? If the code can be cracked, a computer should
be able to simulate it, at least in principle. But
even if a computer could simulate the workings
of the mind, Searle would claim that the machine
would not really be thinking; it would just be acting
as if it were. His argument proceeds thus: if a
computer were used to simulate a stomach, with
the stomach's churnings faithfully reproduced on a
video screen, the machine would not be digesting
real food. It would just be blindly manipulating the
symbols that generate the visual display.
Suppose, though, that a stomach were simulated
using plastic tubes, a motor to do the churning, a
supply of digestive juices, and a timing mechanism.
If food went in one end of the device, what came out
the other end would surely be digested food. Brains,
unlike stomachs, are information processors, and if
one information processor were made to simulate
another information processor, it is hard to see
how one and not the other could be said to think.
Simulated thoughts and real thoughts are made of
the same element: information. The representations
of the world that humans carry around in their heads
are already simulations. To accept Searle's argument,
one would have to deny the most fundamental notion
in psychology and neuroscience: that brains work
by processing information.

It can be inferred that the author of the passage
believes that Searle's argument is flawed by its
failure to
(A) distinguish between syntactic and semantic
operations
(B) explain adequately how people, unlike
computers, are able to understand meaning
(C) provide concrete examples illustrating its claims
about thinking
(D) understand how computers use algorithms to
process information
(E) decipher the code that is transmitted from
neuron to neuron in the brain.

Please explain your answer What is wrong with D

The main argument the author puts forward is how computers and human are processing information.

Searle argues that only thing which distinguishes humans from Computers is the way human uses rational (put reasoning to thoughts) thoughts to understand meaning. PC's, he argues on the other hand uses.
mechanical processes.

option D is irrelevant to the discuss. What difference would it make if Searle is able to understand how computers uses algorithms ? Nothing.. He would still stick to his argument.