B. x-5
The answer is B because:
Step 1: You have to write -7x as a difference
2x^2+3x-10x-15
Step 2: Factor out x from the expression
x(2x+3)-10x-15
Step 3: Factor out -5 from the expression because it is the GCF(greatest common factor) of both -10 and -15
x(2x+3) -5(2x+3)
Step 4: Factor out 2x+3 from the expression
(2x+3)(x-5)
Step 5: Look at equation and see what options listed are present in the equation
Step 6 (optional check): Use foil method for the expression (2x+3)(x-5). You will then get the expression you started out with as an answer 2x^2+3x-10x-15.