The quotient of two numbers is negative. it must be true that

a. neither number is negative

b. one of the numbers is negative

c. both of the numbers are negative

The quotient of two numbers is negative. It must be true that B. one of the numbers is negative.
If neither number is negative, then their quotient will be positive, because both numbers are positive. If both numbers are negative, then their quotient will also be positive.
But since B is correct, their quotient will be negative.
For example: -9/3 = -3