Spot the error in the rule:
'Either' and 'neither' are distributive pronouns. They are used to denote a comparison or choice between two things. They can replace each other in a sentence.
The mistake can be spotted in option C which is “They can replace each other in a sentence”. ‘Either’ and ‘Neither’ are distributive pronouns that refer to a person or thing, one at a time. They are used to denote a comparison or choice between two things, but while ‘either’ is used to convey a positive meaning, ‘neither’ conveys a negative meaning. For example, “Either of the girls is capable of winning” conveys that both the girls are equally talented and have the chance of winning. Whereas “Neither of the girls is capable of winning” means that both will lose. Thus ‘either’ and ‘neither’ cannot be replaced with one another in a sentence since they convey opposite meanings. Since the question is to choose the option with the error, option C is correct. Whereas options A, B and D are incorrect.