Metamorphism can cause which of the following?

• A. Deformation such as faults and folds
• B. Conversion to igneous rock
• C. Reduction in mineral variety
• D. Decrease in crystal size

Answer: (A)

Metamorphism involves changing minerals and textures in a rock while it remains solid, driven by higher temperature, pressure, and directed stress. This stress rearranges minerals and often causes the rock to deform, producing features that record those conditions. In mountain-building zones, rocks are squeezed and stretched, so you see folds and a layered, aligned texture known as foliation as minerals realign and new metamorphic minerals form. That deformation is a hallmark of metamorphic processes tied to tectonic forces.

The option that describes deformation such as faults and folds fits this idea because metamorphism is closely linked to the pressures and stresses that drive deformation and reorganization of minerals. The other statements aren’t representative: metamorphism does not turn rocks into igneous rocks by melting (that’s magma crystallization, though extreme conditions can partially melt rocks, it’s not the normal metamorphic path); it generally creates new minerals (not reduces variety); and crystal sizes typically grow or reorient rather than consistently shrink.