Answer: optio C. 6.
pH measures the acidity of the solutions.
pH 2 is highly acid and pH 12 is highly basic (alkalyne).
You can be sure that the pH of the solution will be intermediate between 2 and 12.
Given that the volumen of the two solutions are equal the pH of the resulting combination cannot be so close to the original solutions. That takes you to eliminate all the options except the option C. 6.
You cannot be sure that the final pH will be 6, because that will depend on the stregths of the two original solutions, that is why the question asks for the most likely resulting pH, and the answer is optio C. 6.