(Solved): (1 point) The reduced row-echelon forms of the augmented matrices of four systems are given below. ...

(1 point) The reduced row-echelon forms of the augmented matrices of four systems are given below. How many solutions does each system have? \( a\left[\begin{array}{lll|l}0 & 1 & 0 & -8 \\ 0 & 0 & 1 & 6\end{array}\right] \) A. Unique solution B. Infinitely many solutions C. No solutions D. None of the above b. \( \left[\begin{array}{rrr|r}1 & 0 & -9 & 0 \\ 0 & 1 & 0 & 0 \\ 0 & 0 & 0 & 1 \\ 0 & 0 & 0 & 0\end{array}\right] \) A. Unique solution B. No solutions C. Infinitely many solutions D. None of the above \[ \left[\begin{array}{lll|r} 1 & 0 & 0 & 3 \\ 0 & 0 & 1 & -19 \end{array}\right] \] A. No solutions B. Unique solution C. Infinitely many solutions D. None of the above \[ \left[\begin{array}{ll|l} 1 & 0 & 2 \\ 0 & 1 & 5 \\ 0 & 0 & 0 \end{array}\right] \] A. No solutions B. Infinitely many solutions C. Unique solution D. None of the above