Sometimes the biological objects are placed in a way, unnatural or unlikely without life. Let us look at the Martian items observed that follow such pattern.
The elaborate item on top would be extremely unlikely to be curved out by the sandblasting, the only element in play on top. The item could be created elsewhere and then moved at the rock top by someone; it could be a creature that get at the rock top itself and died there; it could be a plant that has grown on top from a wind brought seed.
The object on Figure 2 is unlikely to be geologically created, as it has a number of contradictory features.
Its outer surface is smooth, while exposed at the bottom hole internals are structured. Hole on the right has surface, similar to the outer surface. While the outer surface consistent with strong weathering resistance, the internals most unlikely have been created by the water/wind/melting.
The object on Figure 3 is most unlikely to be geologically created, being a thin empty shell inconsistent with being created by elements.