The experimental critical compressibility factor $Z_c$ of most gases lies between 0.27 and 0.30, while the van der Waals equation predicts $0.375$. Which statements are correct?

1. AReal gases at the critical point are denser than the van der Waals equation predicts for the same $P_c$ and $T_c$
2. BThe van der Waals equation is quantitatively inaccurate near the critical point
3. CThe discrepancy means $V_c$ is less than $3b$ for real gases
4. DA gas with $Z_c=0.375$ must be ideal