JEE Main 2021 Mathematics question

Consider the following system of equations : x + 2y – 3z = a, 2x + 6y – 11z = b, x – 2y + 7z = c, where a, b and c are real constants. Then the system of equations :

• (A)has a unique solution when 5a = 2b + c
• (B)has infinite number of solutions when 5a = 2b + cCorrect
• (C)has no solution for all a, b and c
• (D)has a unique solution for all a, b and c