DIRECT Speech because it quotes actual words.Therefore, it has to be changed into INDIRECT Speech.We notice that the REPORTING verb is in the Past tense (‘asked’).When the Reporting verb is in the Past tense, the Simple Present in the Direct Speech becomes the Simple Past in the Indirect (‘is’ becomes ‘was’).While a verb in a question in the Direct Speech is PLACED before the noun/pronoun (‘how is your sister’), it is placed after the noun/pronoun in the Indirect SpeechTherefore, the same sentence in Indirect Speech will be ‘She asked me how my sister was’.Thus, the correct answer is Option 4.All other options are incorrect as they don’t observe the above RULES.