The correct option for the phenomenon of `beats` occurring when the frequencies of two harmonic waves are mentioned to be "nearly same" (option 4).

To understand this better, let`s consider two harmonic waves with slightly different frequencies. When these waves combine, they create an interference pattern known as beats. The beats are characterized by a fluctuation in the amplitude of the resulting wave.

Option 1, "real," is not related to the occurrence of beats and is not the correct explanation.

Option 2, "far apart," also does not correctly explain the occurrence of beats. In fact, beats occur when the frequencies of the two waves are close to each other.

Option 3, "multiples of each other," is not correct either. The occurrence of beats is not dependent on the multiples of each other, but rather on the slight difference in frequencies.

Therefore, the answer provided "nearly same" (option 4) is correct and accurately describes the phenomenon of beats occurring when the frequencies of two harmonic waves are close to each other.