Hypersensitivity refers to pathological immune responses such as dysfunction and tissue damage caused by continuous stimulation by a specific antigen or restimulation by the same antigen. According to the definition above, which of the following is options that are not hypersensitivity? ['Once bitten by a snake, ten years afraid of ropes.', 'Although a certain drug is very effective in treating gastrointestinal diseases, some patients experience dry mouth and palpitations after taking it.', 'A hypothyroidism occurs in a whole-body after a long-term use of hormones.', 'After a penicillin skin test, a patient has enlarged lymph nodes.']