Since the order of selection does not matter, we will use combinations to solve this problem.
We are to form the combination of 30 objects taken 6 at a time. This can be expressed as 30C6.
[tex]30C6= \frac{30!}{6!*24!} \\ \\
= 593775 [/tex]
This means the six teachers can be selected in 593775 ways.
So the correct answer is option A