The answer is A. 3x ≤ -6.
Three times a number is 3x. Negative six is -6. But, how to solve the inequality?
At most -6 means that 3x can be -6 or less. If it was said at least -6, that it would mean that 3x can be -6 or more.
So, three times a number is at most negative six can be expressed as:
3x ≤ -6