No computer will ever be able to do everything that some human minds can do, for there are some problems that cannot be solved by following any set of mechanically applicable rules. Yet computers can only solve problems by following some set of mechanically applicable rules. Which one of the following is an assumption on which the argument depends? ['Every problem that is solvable by following more than one set of mechanically applicable rules is solvable by almost every human mind.', 'At least one problem not solvable by following any set of mechanically applicable rules is solvable]e by at least one human mind.', 'At least one problem solvable by following some set of mechanically applicable rules is not solvable by any human mind.', 'Every problem that is solvable by following at least one set of mechanically applicable rules is solvable by at least one human mind.']