If a researcher performs a meta-analysis and finds that the meand= 0.11, and that the 95 percent confidence interval around this mean is (-0.04, 0.26), what could the researcher conclude?

Averaging across all of the literature, there really is no effect.

Averaging across all of the literature, there is a strong effect, and this effect is statistically significant.

There is a strong effect, but it is unclear what the direction of the effect is.

All future studies of this effect will find effect sizes somewhere between 0.34 and 0.56.