<prompt>  A 17-year-old boy presented with TLC of 138 × 109 L with 80 blasts on the peripheral smear. Chest X-ray demosnstrated a large mediastinal mass. Immunophenotyping of this patents blasts would most likely demonstrate -No surface antigens null phenotypeAn immature T cell phenotype TdtCD34CD7 positveMyeloid markers, such as CD13, CD33 and CD15B cell markers, such as CD19, CD20 and CD22 