If $R(\tau)$ is the autocorrelation function of a real, wide-sense stationary random process, then which of the following is $\text{NOT}$ true?

- $R(\tau)=R(-\tau)$
- $|R(\tau)| \leq R(0)$
- $R(\tau)=-R(-\tau)$
- The mean square value of the process is $R(0)$