A sentence which contains a verb in the simple past tense is C. She obeyed her father.
Simple past tense is used to depict an action that existed or happened before now. It is the basic form, action duration is not important as it can be in the distant past or recent past.
Certain time expressions are associated with a simple past tense that is:
Hence, in the above sentence, it uses a definite point in time "obeyed her father."