The Superposition of Two Waves And $y_{2}=(0.006 \mathrm{~cm}) \cos \left[2 \pi\left(\frac{150}{\mathrm{~s}} t\right)\right]$

The superposition of two waves and $y_{2}=(0.006 \mathrm{~cm}) \cos \left[2 \pi\left(\frac{150}{\mathrm{~s}} t\right) \right]$ at the location x = 0 in space results in:

A) beats at a beat frequency of 3 Hz.
B) a pure tone at a frequency of 153 Hz.
C) a pure tone at a frequency of 156 Hz.
D) beats at a beat frequency of 6 Hz in a 153 Hz tone.
E) a tone at a frequency of 156 Hz, as well as beats at a beat frequency of 6 Hz in a 153 Hz tone.