Question

  

Answer 1

\(A=\left\{2\right\};B=\left\{2;3;5;7\right\}\\ A\subset X\subset B\\ Vậy:X\in\left\{\left\{2\right\};\left\{2;3\right\};\left\{2;5\right\};\left\{2;7\right\};\left\{2;3;5\right\};\left\{2;3;7\right\};\left\{2;5;7\right\};\left\{2;3;5;7\right\}\right\}\)

Có 8 tập X thoả mãn => Chọn D