$$Average\left(arithemetic\ mean\right)=\frac{summation\ fx}{summation\ f}$$
$$Average\ salary=\frac{total\ salaries}{number\ of\ professors}$$

Statement 1=> At university M, the budget allocates $3500000 for faculty remuneration
At university M, salary budget = $3500000
The total number of professors is unknown so the average salary at university M cannot be evaluated. Statement 1 is NOT SUFFICIENT

Statement 2 => At university D, the budget allocates $6000000 for faculties salaries
At university D, salary budget = $6000000
The total number of professors and information on university M is unknown so no data for comparison. Hence, statement 2 is also INSUFFICIENT

Combining both statements together =>
None of the statements gives the total number of professors in the university so both statements combined together ARE NOT SUFFICIENT

Answer = E