Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) esophageal atresia/tracheoesophageal fistula ?
    ### Response:
    Esophageal atresia/tracheoesophageal fistula (EA/TEF) is a condition resulting from abnormal development before birth of the tube that carries food from the mouth to the stomach (the esophagus). During early development, the esophagus and windpipe (trachea) begin as a single tube that normally divides into the two adjacent passages between four and eight weeks after conception.
    