Which of the following frequencies does not belong to FM broadcast.

FM (Frequency Modulation) broadcast operates in the frequency range of 88 MHz to 108 MHz.

Let us check each option:

1. 106 MHz - Falls within 88-108 MHz range. This belongs to FM broadcast.

2. 64 MHz - Falls outside the 88-108 MHz range. This does not belong to FM broadcast.

3. 99 MHz - Falls within 88-108 MHz range. This belongs to FM broadcast.

4. 89 MHz - Falls within 88-108 MHz range. This belongs to FM broadcast.

Therefore, 64 MHz does not belong to FM broadcast.