Answer:
OPTION C: 2x - y = -1
Explanation:
Equations of two straight lines do not have a solution when they do not meet. Also, two parallel lines never meet.
Given the equation of the first line is: 2x - y = 1. So, the line parallel to this line should be the answer.
Note that the equations of two parallel lines only differ by a constant.
i.e, If ax + by + c = 0 is an equation of a line then the equation of the line parallel to this would be ax + by + k = 0.
Hence, the required answer is: 2x + y = -1, which is OPTION C.