Which of the following is the conjugate of 6 + 7i?

The conjugate of a complex number is obtained by changing the sign of the imaginary part. In this case, the complex number is 6 + 7i.

To find the conjugate, we take the real part (which is 6) and the imaginary part (which is 7) and change the sign of the imaginary part. Thus, the conjugate of 6 + 7i is 6 – 7i.

So, the answer to the question is that the conjugate of 6 + 7i is 6 – 7i.